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  Topic: Audio streaming errors (5 replies)
#1     Sun Jan 08, 2012 9:14 pm
AA7FV
Tucson, Arizona
 
Join Date: Dec 2010
Posts: 4
Subject: Audio streaming errors

I have read the helpful FAQ comments and suggestions about audio breaking up, and what might be done to improve the situation.

I find the worst aspect is that there is no warning given that this problem is, or might be, happening. I just monitored myself, sending CW via an external keyer, and found that as received over the Internet on a second computer, about one CW letter in every 6 sent is being lost. Until I monitored myself, I optimistically believed that my audio - especially my CW transmission - was being received perfectly. Would it be possible for some warning indicator to appear, either at the sender or the receiver, whenever the Internet transmission might be dropping (in this case) characters?

Better still, notwithstanding the helpful FAQ advice, is there any way that the occasions of dropped audio could be reduced within the program? Given the low bandwidth needed by the program, I wonder if it's somehow possible to improve the performance?

Apart from this, thanks for a great program.
73, Darrel, aa7fv.
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#2     Mon Jan 09, 2012 4:51 pm
VE3EFC
 
Join Date: Aug 2006
Posts: 724
Subject:

This problem can be entirely solved if CQ100 used larger audio buffers. A lag of 20 to 60 seconds would allow all network gaps to be filled before they are sent to the sound card.

Currently, CQ100 is designed to reduce the lag at the expense of dropouts. If the received audio gets one second behind, we drop some audio to catch up on the lag. A few people who have overloaded internet, or intermittent networking will experience lots of these dropouts. Other people may be able to listen for several minutes before there is this one second dropout. These dropouts are usually not noticed on voice, but are more obvious on CW.

If you are hearing these dropouts on your own transmission, it does not mean everyone else is hearing the same problem. Do you hear the same dropouts on the CW practice stations?

The FAQ has some advice how to improve these dropouts. The first thing I would try is to connect a wire to your internet instead of using a wireless connection. Be sure some other computer is not uploading on your internet. Uploads are more sensitive than downloads. Try closing all other programs.
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#3     Tue Jan 10, 2012 4:01 pm
AA7FV
Tucson, Arizona
 
Join Date: Dec 2010
Posts: 4
Subject:

Thanks for the helpful response.
I have not noticed the problem on the CW practice programs, although I have noticed it sometimes listening to other CW stations, and other stations often comment on dropouts on my own CW transmissions. I don't use the CW keyboard - would that be better? The problem persists even after closing other programs in my own computer. I have not yet tried using a wired connection, which is a little difficult more difficult to arrange locally. I've normally considered my Internet connection quite robust - and often using video streaming, for example, without any difficulty.
The FAQ on this topic is very helpful, but apart from trying to arrange a wired connection instead of wifi, I have tried all the other suggestions without obvious improvement. My impression is that the problem is worse at some times than others, which probably results, as you say, from variable Internet loading. As you can appreciate, with about one in 6 CW letters apparently being lost, I'm reluctant now to engage in CW QSOs on CQ100 at all.
Thanks again for your help,
best regards,
Darrel.
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#4     Thu Jan 12, 2012 9:49 am
AA7FV
Tucson, Arizona
 
Join Date: Dec 2010
Posts: 4
Subject:

Would it be possible to give the user some control over the size of the audio buffer? I would gladly accept a few seconds of latency in order to reduce the occurrences of my CW characters being dropped.
Thanks for your help,
Darrel, aa7fv.


VE3EFC wrote:
This problem can be entirely solved if CQ100 used larger audio buffers. A lag of 20 to 60 seconds would allow all network gaps to be filled before they are sent to the sound card.

Currently, CQ100 is designed to reduce the lag at the expense of dropouts. If the received audio gets one second behind, we drop some audio to catch up on the lag. A few people who have overloaded internet, or intermittent networking will experience lots of these dropouts. Other people may be able to listen for several minutes before there is this one second dropout. These dropouts are usually not noticed on voice, but are more obvious on CW.

... ... ...
.
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#5     Thu Jan 12, 2012 6:39 pm
AA7FV
Tucson, Arizona
 
Join Date: Dec 2010
Posts: 4
Subject: Audio streaming errors

After some tests, I find that when sending CW to the same (transatlantic) station using the CQ100 keyer and keyboard, there are very few errors. However, when sending CW via an external keyer audio into the computer mic input, between 1 in 6 and 1 in 8 CW letters are dropped.
Is it obvious why CW originating from the keyboard propagates almost without error, while CW sent via audio into the mic is so much more demanding on a good internet connection?
Thanks,
Darrel, aa7fv.


VE3EFC wrote:
This problem can be entirely solved if CQ100 used larger audio buffers. A lag of 20 to 60 seconds would allow all network gaps to be filled before they are sent to the sound card.

Currently, CQ100 is designed to reduce the lag at the expense of dropouts. If the received audio gets one second behind, we drop some audio to catch up on the lag. A few people who have overloaded internet, or intermittent networking will experience lots of these dropouts. Other people may be able to listen for several minutes before there is this one second dropout. These dropouts are usually not noticed on voice, but are more obvious on CW.

If you are hearing these dropouts on your own transmission, it does not mean everyone else is hearing the same problem. Do you hear the same dropouts on the CW practice stations?

The FAQ has some advice how to improve these dropouts. The first thing I would try is to connect a wire to your internet instead of using a wireless connection. Be sure some other computer is not uploading on your internet. Uploads are more sensitive than downloads. Try closing all other programs.
__________________
#6     Sat Jan 14, 2012 12:05 am
VE3EFC
 
Join Date: Aug 2006
Posts: 724
Subject:

hmmm this is an interesting discovery. Mic generated audio and keyboard generated audio are treated exactly the same. If the keyboard audio works fine, then we don't have a networking problem. Perhaps its a sound card problem.
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