Computer based voice keyer queation

km9r.mike

My audio .wav file is stored in my PC and N1MM+ accesses that file when a function key is pressed in N1MM+, however, sometimes the wav file does not play cleanly. When it does this it plays at approximately 92% of full rate and sounds jittery. I can not determine what is causing this and of course how to correct it for 100% reliable playback. 

I have tried to change many settings on SSDR and N1MM+ to resolve the issue but no luck, however, this leads me to think that it may a PC based issue.

I do know that when I play the audio wav file ( both SSDR and N1MM+ running ) with the MS voice recorder program it faithfully reproduces the file 100%. However, when N1MM+ commands that the wav file to play, it will only play correctly about 75% of the time.

I also know this is not an RFI issue because it also occurs when the SSDR power slider is at
0.0 watts.

Any suggestions on how to resolve this ? I have an i5 Dell 660 win10 pro and latest SSDR.

Al K0VM

Mike,
  It might be caused by a DAX condition...If its a case where it works for a while and then it goes bad, try stopping and restart the DAX control panel.  Its likely that this may cure it ( temporarily ).

I dont know what exaclty triggers this condition but is seems related to window/PC/networking.latency (DPC's) issures.

AL, K0VM

km9r.mike

I have not tried closing and restarting dax yet. I have used , however, the dax  voice stream, literally, over a hundred times to record the messages into the audio file and have zero problems with that. So dax is faithfully transferring my message to the MS voice recorder every time. 

I did fail to mention that when the wav file is not being faithfully reproduced while N1MM+ has the repeat function engaged, the issue of jittery playback can resolve itself and nice clean audio will be sent, however, it can revert back to jittery.

I will mess around with closing and restarting dax to see if that will help the issue. Please keep in mind that I have about zero experience with voice keyers.

Thanks Al

Al K0VM

You may also wish to verify that your record/playback samples rates are consistent. 48Kbps or sub-multiple (e.g. 24,12, 8 ).

AL, K0VM

km9r.mike

Just a quick follow up. It appears that may be my issue. Before, like I originally stated the bad playback would occur about 75% of the time while using N1MM+ with no rhyme or reason. I just finished engaging the cq loop feature on N1MM+ multiple times. I would let it play until the jittery playback occurred (approx. after 10 cq repeats ) at which time I would stop the playback feature in N1MM, close dax, restart dax and re engage the cq repeat function. Each time I did this the playback would be reliably nice and clean for about another 10 to 12 repeats then jittery would reappear. Hopefully reliability can be improved to 100% this is a neat feature.

km9r.mike

I thought that a difference in sample rates may be an issue as well, but that darn MS voice recorder is not too user friendly wrt allowing a change in settings. Thanks for the things to look at Al. I only been playing with it for two days now and I will keep your help in mind when trying to resolve this.

Al K0VM

Try using Audacity ( free) .. 
The DAX issue seems somewhat related to the ablity of the PC to handle multitasks
without encountering long Delayed Procedure Calls (DPC's). More PC is better.
AL, K0VM

km9r.mike

I have been playing with it more and while the restarting of dax appears to help, I think it reoccurs too soon for it to be dax related and think it may be an issue of a **** pc and multitasking. I am gonna utilize the MS pc monitoring program and see if I can determine if it occurs during peak demands only. It does sound as if the pc is struggling to get the words out : )


When it works, it works great and has great quality. About one out of every 10 is jittery/fluttery but that will disappear on the next repeat but then will reappear, I have noticed when I command a playback of my call, when the flutter playback occurs it appears to repeat for a longer duration the quicker I command N1MM to playback my call (ie placing more demand on the PC). I am guessing once the PC recouperates then the flutter goes away.