I have both applications set to use "DAX Audio TX (FlexRadio System" in the sound card settings.
I tried leaving the DAX Control panel open while doing this thinking the TX Streeming botton would be yellow or red but it remains blue.
This has been going on since before the latest SSDR upgrade. I feel it it some sort of Windows thing.
Radio: Flex 6500
Operating Sys: Win10
SSDR: 1.10.8.39
Thanks
73
Kent
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Posted 3 years ago
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Gary
K6HN
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By any chance, could it be related to a user/file permission thing, or a 3rd party security software issue. I'm always having to re-enable permissions with my setup. Luckily I usually see a popup/nag/warning when the blockage happens.
SDRgadgets
73, Jay - NO5J
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I never see anything pop up, no errors or security warnings so I would have to say that it is not a file permission problem. Just no sound.
Thanks
Kent
NC6B
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I'll be looking into reproducing the problem. I haven't seen it yet, but I'm going to be looking into Winwarbler in hopes it might be a solution for multi-slice digital app logging. So I might run into the same difficulties.
SDRgadgets
73, Jay - NO5J
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WW is a great program. I started using the DXLabs suite about a year ago. The support is great!
I may call FRS tomorrow and see if they have a fix for my problem.
Thanks
Kent
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Tim - W4TME, Customer Experience Manager
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Are any of the DAX sound devices be marked by Windows as the default sound device? If so, this could be causing your issue.
Also, does simply shutting down WSJT and restarting it fix the issue? If so, then I'd focus my attention on that rather than a DAX issue.
If shutting down WSJT does not fix the issue, but shutting down the DAX control panel and restarting it fixes the issue, then I'd start investigating the possibility that your PC is experiencing some long duration DPC errors that may be causing some buffer corruption issues. Windows really isn't a good operating system for handling real-time audio and DPCs can exacerbate the problem.
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Something was very strange. I checked my Windows default devices in Playback and Recording. Under Recording the default device was DAX Audio TX. I know I had set it to the Mic on a webcam that I have a few months back. I changed back to the webcam and restarted the PC. After the restart DAX Audio TX is now under the Playback tab. Is that where it is suppose to be?
I will speculate that when I did the SSDR 1.9.13 install, back in October, Windows changed the default device to DAX Audio TX in the Playback ( I really hate Windows) and that is when the problem started.
As for the problem I will leave WW open for a while and comeback and check in a bit. I will post later this afternoon to confirm the problem is solved.
Thanks
73
Kent
NC6B
Tim - W4TME, Customer Experience Manager
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Windows will enumerate the sound devices and reassign the default device any time there is a change in the installed sound devices. This is why I am so adamant about not uninstalling DAX when you remove a version of SmartSDR so a re-enumeration is never triggered.
Windows has this annoying feature of not making a sound device active unless it is physically installed, so if you plug a mic into your PC sound card, that port becomes active and Windows re-enumerates all the installed sound devices. This is why I keep a pair of headphones plugged into my PC sound card all the time and designate them as the default sound devices.
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Stopping and starting DAX did not fix the problem.
Tim - W4TME, Customer Experience Manager
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Tim - W4TME, Customer Experience Manager
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Kent
Tim - W4TME, Customer Experience Manager
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So using Fldigi, The problem does not happen. I have checked several times now and I do not lose the audio. Im not sure what this means. Is the problem with DXLab, WSJT-X, WinWarbler ot Windows?
Kent
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I'm also running a 6500, V1.10.8.3, Win10
WSJT-X, Winwarbler 8.8.7 (and the rest of the DXLabs suite) and N1MM
I have not seen any issues with audio output switching from device to device at any time. I don't run WSJT-X much, but Winwarbler is up pretty much 24/7.
I just left WJST-X up (Winwarbler up at the same time) for the last 20 minutes, transmitted as it should.
I do have the speakers in one of my monitors set as the default playback device.
This info may be of zero help, but our setup is similar, so I'm throwing it out there.
Tom
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Thanks.
I think at this point it may be a Windows problem that I may just have to live with.
Kent
Tim - W4TME, Customer Experience Manager
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Exactly what is it that these two applications could be doing to cause this behavior, Tim?
Tim - W4TME, Customer Experience Manager
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I suspect it may have something to do with the type or version of the audio APIs the apps are using. I believe WSJT is using PortAudio.
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Don't forget the Human element, aren't many of the trouble reports related to that?

Prove me wrong people!
SDRgadgets
73, Jay - NO5J
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"I can see in the Sound Window that the level is moving on "DAX Audio TX". After a while I try to transmit and the level no longer moves on the "DAX Audio TX" but the level now moves on "DAX RESERVED MIC AUDIO".
Tim - W4TME, Customer Experience Manager
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Jay - the audio setup is straightforward; you set the input and the output to the appropriate sound device. There are usually no other parameters to set (mess up).
Dave, like I said, I don't know what is wrong. Apps like Fldigi just work and work reliably unless there is audio buffer corruption due to long duration DPCs. But we do not get reports of Fldigi just acting weird like this or stop working altogether. Others do not. It does not indicate something being systemically broken in DAX.
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To err is Human, insisting your right, is a known Human error. Maybe I'm wrong about that too. Can I blame others for that? Once in awhile maybe. But, the laughter is upsetting. YMMV, but my mileage gets me somewhere.

SDRgadgets
73, Jay - NO5J
Tim - W4TME, Customer Experience Manager
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"I Well, I ain't always right but I've never been wrong.
Seldom turns out the way it does in a song.
Once in a while you get shown the light
In the strangest of places if you look at it right."
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I know Dave AA6YQ is watching this and my observation is the only thing in common with the 2 applications is they are controlled by DXLab.
I think the next thing I try will be to set up WSJT-X in a standalone setup and see if the problem happens.
As a last resort I may format the drive and do a clean install of windows.
Thanks
Kent
Tim - W4TME, Customer Experience Manager
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As I said "last resort" and Im not there yet!
Thanks
Kent
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Kent, in a post earlier in this thread, you said that the problematic behavior first appeared "when I did the SSDR 1.9.13 install, back in October". Have you tried reverting to the version of SSDR you were using before you made this change?
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Dave, I have just downgraded SmartSDR to the previous version 1.9.13 and will try to reproduce the problem. If the problem happens I will downgrade again and see what happens.
Thanks
Kent
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Is there a way to tell if the DAX Audio TX has been turned off by Win10??
Kent
Tim - W4TME, Customer Experience Manager
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Go to Device Manager. First look for your devices in Audio inputs and outputs. Double click on one of the devices and check the Device status. It should say "This device is working properly."
A disabled device would have a status such as: "This device is disabled. (Code 22) Click Enable Device to enable this device."
While you are at it, scroll down on the list to Sound, video and game controllers and check the FlexRadio Systems audio devices there.
Also check you don't have any conflicts or unknown devices. This is usually indicated with a "!" beside the device. I think you are going to find everything is enabled properly. This doesn't sound like something Windows is doing on purpose.
I've been following the thread. I have always had a problem with WSJT-X where, randomly, it would just stop sending any tones. The rig would key and everything would look good except the power was way way down and there would obviously be no audio. For me, it doesn't happen on schedule. Maybe once every day or two or three. Restarting WSJT-X brings it back to life. I don't use WinWarbler so I can't tell you if the same happens to me. I do use fldigi and I cannot recollect an audio out problem with that.
Tim mentions above WSJT-X might use PortAudio. Not sure why he mentioned it or if there's a clue there. Fldigi uses PortAudio also.
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When it does happen go look in the Windows Sound Control panel. Look at the level meters when you try to transmit. Mine switches from the DAX Audio TX to DAX RESERVED MIC AUDIO. I suspect yours will be the same. Like this:

Kent
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Tim - W4TME, Customer Experience Manager
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It is a Microphone on a USB Webcam that I have.
Kent
Tim - W4TME, Customer Experience Manager
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No the button for the Mic Stream says off.
Kent
Tim - W4TME, Customer Experience Manager
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Now if you are seeing audio levels indicated indicated on the DAX RESERVED MIC AUDIO device (playback) and on the DAX Mic Audio device (recording) in the Windows Sound Control panel when the Mic Stream DAX channel is off, and you did not make any changes to the radio, either manually or via a third-party application that can control the radio (CAT or an app using the FlexLib API), then something has messed with the DAX audio devices.
This is why I made a reference to PortAudio previously. Windows allows multiple audio APIs to manipulate sound devices. It is possible PortAudio has opened the DAX RESERVED MIC AUDIO device and is passing an audio bit-stream audio to it.
There is another possibility and this one is probably a little more plausible. You are using a USB audio device and it is your default device in the recording tab. This is a transient device, meaning that is it becomes disconnected, be it from powering down, physically disconnected or some other way, Windows is going to re-enumerate the audio devices. If this happens and the third-party app is assigning an audio pin (sound device) based on an index number, then it is very possible that the third-party app is not handling the state change well and could end up reassigning the audio output and passing audio down a different device in the playback tab, like the DAX RESERVED MIC AUDIO device. Bluetooth headsets and USB speakers are also transient audio devices.
If possible, what I'd to test this is to connect a set of speakers and a mic to the PC's embedded sound card and assign them as the default recording and playback devices. This configuration will not change and should prevent the
re-enumeration and subsequent reassignment of the Windows sound devices; essentially a more stable configuration. If this shows positive results, then I think the trigger mechanism has been found. The fix would be a fix to the third-party digital mode app to handle these re-enumeration state changes better.
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Ok I have an old headset that I can hookup to the plugs directly on the sound card. I will then reboot the PC and if the mic and headphones have not been assigned as default I will make them that way then reboot again just to be safe.
I will let you know the results.
Kent
Tim - W4TME, Customer Experience Manager
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No joy!
The audio still switches to DAX RESERVED MIC AUDIO.
Do you think I should uninstall Smart SDRand then reinstall? Do you think it will make a difference??
Kent
Tim - W4TME, Customer Experience Manager
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Tim - W4TME, Customer Experience Manager
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I do not think reinstalling SmartSDR (specifically DAX and the virtual audio drivers) will make any difference. If you were seeing the same type of issue with all applications where you can assign DAX sound devices to them, then I'd be more inclined to take this approach.
I installed the latest version of WSJT-X last night and have been running it in WSPR mode for a little over 12 hours and it just works.
I do have one question. Are you doing any band hopping? That may be a trigger (I am not doing band hopping).
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I mainly use WSJT-X for JT65 and JT9 so no band hopping.
Could a transmit profile that I created be causing this. I created a transmit profile for WSJT-X that I just noticed was in the Global profile also. I did not make the one in Global. I have deleted both profiles in Global and Transmit. I am now going to try things out.
If that does not work Im going to uninstall and reinstall SSDR and DAX. It wont hurt to try.
Kent
Tim - W4TME, Customer Experience Manager
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When I uninstall SSDR and DAX should I uninstall all versions of SSDR? I have 3 versions installed now. Also do I uninstall Flex VSP separately or does it uninstall with SSDR?
Kent
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One obsevation, After the reinstall of SSDR v1.10.8 the default playback sound device was changed to DAX RESERVED MIC AUDIO. I changed it back to the speakers I have connected to the rear of the PC. The default device in Recording was not changed from the mic on my headset.
Kent
Tim - W4TME, Customer Experience Manager
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https://helpdesk.flexradio.com/hc/en-us/articles/204975589-How-to-do-a-Complete-uninstall-of-SmartSD...
The reassignment of the default playback device is all due to Windows mucking with things when sound devices are disabled or removed.
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I have uninstalled and reinstalled SSDR and DAX according to the directions above.
I am optimistic, I have had WinWarbler open for an hour now and it continues to transmit with audio. I will leave the radio on for a few hours and comeback and give it a check.
Kent
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Now after a few hours the problem has not happened again.
If it happens again Im going to put a different SSD in my PC and install everything from scratch.
Thanks for sticking with it!!
73
Kent
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The issue is solved on mine. It was fairly painless. Just completely uninstall SSDR as described above.
Kent
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Kent
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I open the Sound window. I scroll down to "DAX Audio TX". When I first open WinWarbler and transmit all is fine. I can see in the Sound Window that the level is moving on "DAX Audio TX". After a while I try to transmit and the level no longer moves on the "DAX Audio TX" but the level now moves on "DAX RESERVED MIC AUDIO".
Why is the audio changing from one to the other??
Kent
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If I change the soundcard settings in WinWarbler to "DAX RESERVED MIC AUDIO", thinking the audio would then happen it does not. The level now moves on "DAX RESERVED IQ RX 4".
Kent
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That did not work. No sound was played through the speakers.
Kent
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Tim - W4TME, Customer Experience Manager
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I eventually reinstalled Win10 and the problem is gone. It must have been a Windoze problem.
Thanks Tim and all that helped.
73
Kent
NC6B
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After monitoring only every 14 min I loose control of decoding in both PSK31, JT65 ETC
Does the upgrade to V2.0 fix this issue?
Ian
Tim - W4TME, Customer Experience Manager
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Here are some relevant HelpDesk articles on the subject.
https://helpdesk.flexradio.com/hc/en-us/articles/202118398-What-are-DPCs-and-why-do-they-matter-
https://helpdesk.flexradio.com/hc/en-us/articles/202118698-Using-LatencyMon-to-collect-DPC-Latency-D...
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I pulled my hair out for a long time with this. The only way I found to fix the problem was to reinstall Win10. It was fairly painless. I just backed up my personal files but if you go through Win 10 settings then "Update & security then "Recovery" It will keep all of your files in their original locations. When I reinstalled the programs most of my file were still there so it was not that hard to get things going again. It was just time consuming. The problem has not come back since.
Sorry!
Good luck
73 Kent
NC6B
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Thanks for those tips and program I was able to track down the problem the past 3 hours all is working well.
Ian
Tim - W4TME, Customer Experience Manager
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