2.1.33 Dax/Cat somewhat unstable...

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It seems roughly since 2.0 that Dax and perhaps Cat have become increasingly unstable.

Today on my new laptop, Core i7, brand new installs of SSDR 2.1.33 and WSJT-X etc I was working FT8 on 20m.

I would make a few contacts then I would notice even though the bar was yellow in WSJT-X indicating transmit that the rig was not transmitting.

Shutting down WSJT-X and restarting Dax usually fixes it.  But it seems like I can only go about 5 contacts before a software restart is required.

This could be WSJT-X as I am using 1.8 with compiled in stuff for the 6600 to work.  But still I sometimes see that Dax TX channel stops working.  A restart of both WSJT-X and DAX will fix for a short while.

Kind of really annoying and makes the mode way less fun to operate.  Anyone else seeing issues?
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Mark - WS7M

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Posted 1 year ago

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David NT8Y

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This has been similar for me. I have a 6600M, Core i7 @3.6 GHz desktop, SDR 2.1.33 and WSJT-X v1.9.0-rc2. I thought my profiles had issues, I would rework and save them, it would work either all day or for a short time. I decided yesterday to reload the DAX drivers, In fact I used your DAX Fix bat files modified to my version and directories. Last night all was good. I'll see what today brings. I have been very pleased with the 6600M so far otherwise.
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Mark - WS7M

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I can confirm this behavior on two different Win10 computers.  

I have a brand new RazorBlade laptop.  Core i7, 16gb, fast, fresh Win10.  Yesterday I was having to restart DAX 2-4 times during a 2 hour FT8 session on 20 meters.

The behavior is that everything appears ok but DAX TX stops working.  IE no output.  

A shutdown of WSJT-X restart of DAX will fix it for a short while.

This morning I used my Win10 desktop which has prior to my 6600 arriving been running my 6500 and I have done literally all day long FT8 sessions without issues.   I made two QSO to Canada then suddenly could not TX any more.

Once again DAX is dead.  During TX the TX streaming has no signal.   Restarting WSJT-X does not fix it.  I must restart DAX then restart WSJT-X.

Don (SliceMaster Don) suggested I try SliceMaster to control the radio.  I gave that a try this am but I have a different problem with that...   I've emailed Don.

I guess there is always the possibility of FRI but I really have not changed a thing except to swap in the 6600 in place of the 6500.  I will try running with low power for a while and see if things get better but I am suspecting the issue is with DAX.

@David:  Yes this is frustrating.  I am hopeful your reload works.  I was on 2.1.30 with my Flex 6500 for a long time and did not upgrade to .32 or .33 until very recently, almost right before receiving my 6600.   I can remember running FT8 for very long periods of time without issue.
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David NT8Y

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The 660M replaced my 6500, however I was not delving into digital wotldon the 6500. All morning and early afternoon all has been well since I reloaded the DAX drivers.
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Jon - KF2E

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Mine stops transmitting as well. In my case however I usually find that DAX has deselected transmit and the by selecting it again I can work for a while longer. 
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Mark, are you running the LT wireless ? If so have you tried it direct to the radio. Just wondering because I seem to have some issues myself but am blaming it on being wireless.
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Tim - W4TME, Customer Experience Manager

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Official Response
There is not any evidence that there have been increased instability issues with CAT and DAX since v2.0 was released.  There have been no changes to CAT and DAT in a long while other than adding SmartLink support for CAT.   However, we have seen an increase of issues related specifically to WSJT-X in Support, but during the same time, almost no reports with other CAT enabled third-party software.  Anecdotal evidence points to an issue with WSJT-X and not specifically to CAT and DAX.

Enve this post has a common thread; WSJT-X

Now I am not saying there isn't an issue with DAX, as we have acknowledged that there is something environmental with certain PC configurations that causes DAX buffer corruption that is resolved by closing and restarting DAX, but it does not affect everyone.  I can run my AMD machines for days constantly decoding digital modes with Fldigi and I never experience the issue.
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My 6700 is using 2.1.33 and Windows 8.1

I started using CW Skimmer a few weeks ago and noticed a few times a week that the waterfall will either go blank or be completely filled with garbage. In both cases decoding stops until I stop and restart DAX then all is well. I usually have to do this 2 or 3 times a week.

I have experienced DAX problems prior to the SSDR upgrade when using FT8 and again the only fix is to reboot DAX. I saw a thread a while back stating that DAX has known issues and was going to be fixed in the near future so I didn't bother reporting it.

What is the status of these known DAX issues?
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Mark - WS7M

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Tim and all,

Well the DAX corruption problem is real.  It happens on both of my intel PCs.

It seems that it is worse even though you claim not changes and I trust that.  But still the problem is real and very annoying and in some cases makes doing any digital work almost useless.

I hope there is a fix it ticket for this issue.