WNDR4300 Static every 230 seconds on Dragonfly Black 1.5

Installing and Using OpenWrt
1

Like the title says, I get a low screeching sound every 230 seconds on a Dragonfly Black 1.5 USB DAC when playing music from any source using ShairPlay, Shairport-Sync, or MPC over alsa. A cheap 16 bit DAC I also use does not have this problem. Before I upgraded to 19.07.4 from 19.07.2 the noise was happening every 60 seconds.

Any ideas on how on how to further debug this? I watched Top and don't see anything usual when the static happens. I think I read there may be some USB issue with the WNDR4300, but it seems like some process must be doing a lot of interrupts periodically or something.

The 16 bit DAC sounds ok, but I have some higher def music I want to stream also. I have another higher resolution DAC that doesn't have the issue either.

TIA!

2

running snapcast client on wndr4300 out a zalman zm-rssc without issue.

i would probably move some test audio locally (it is a shame alsa-utils doesn't seem to include speaker-test) and run a serial cable for console, then begin stopping network interfaces and processes. might be able to find the issue. though the fact other dacs don't have the noise is strange.

3

Thanks for the reply, blackcat.I could probably setup a snapcast test although straight up mpc form an nfs share showed the same issue.