"fix" for audio dropouts with Motorola radios and mmdvmhost...

Help with DMR issues
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KC1LKO
Posts: 3
Joined: Mon Sep 27, 2021 2:06 am

"fix" for audio dropouts with Motorola radios and mmdvmhost...

Post by KC1LKO »

I put "fix" in quotes as I am not sure yet why it makes go away the symptom whereby sound being received degrades then corrects itself on transmissions of about 35-40 seconds or longer, specifically on Motorola radios (at least the 7550e, 5550e, SL7550e variants)

The "fix" is to set jitter to 0 (default is 360) in the DMR Network section of the MMDVMhost expert settings in pi-star. (Found this by experimenting as I kept increasing it first, but all it did was to add latency...)

I started to look at code in mmdvmhost and suspect something related to resetting of timers, but have not spent sufficient time to validate things.... did not want to keep waiting to find out real reason why the symptom goes away, but I have 4 radios and many hotspots (13+) and this symptom happens on those running mmdvmhost based software such as pi-star (does not happen on openspot3 for example).

Will continue looking at code/experimenting... putting this out there in case it helps someone and/or in case someone says "aha!, I know why! "

Thanks and 73

Miguel/KC1LKO
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