08-27-2020, 07:59 AM
Hi everyone, I'm using a RPi zero W with an Allo miniboss DAC. It's working very well overall but I get problems with upsampled audio (whether done on my computer player or locally on moode), which I'd like to do more due to the DAC only deactivating its processing at 384 KHz. What happens is that I generally get garbled audio and pauses at the start of tracks, and then it works well once a track is finally launched.
I know that the RPi ZW has a pretty lousy CPU and that's its mostly to blame, but I looked a bit more into this today, and it looks like there is enough headroom for the CPU to do the upsampling, as the mpd utilization once the song is launched is around 40-50%. What seems to be happening is that the wifi driver (kworker/u2:2-brcmf_wq/mmc1:0001:1 AND irq/86-mmc1) hogs the CPU when the track is being received all at once at the start. This also explains perfectly why it's garbled at the start but is fine once the data has been received.
Given these elements, is there anything that would be possible to try to solve this, such as reducing wifi CPU priority, capping network speeds or forcing moode to receive parts of the tracks little by little so that I don't get this spike at the start ? I haven't found any options in my player to do so (Audirvana).
I know that the RPi ZW has a pretty lousy CPU and that's its mostly to blame, but I looked a bit more into this today, and it looks like there is enough headroom for the CPU to do the upsampling, as the mpd utilization once the song is launched is around 40-50%. What seems to be happening is that the wifi driver (kworker/u2:2-brcmf_wq/mmc1:0001:1 AND irq/86-mmc1) hogs the CPU when the track is being received all at once at the start. This also explains perfectly why it's garbled at the start but is fine once the data has been received.
Given these elements, is there anything that would be possible to try to solve this, such as reducing wifi CPU priority, capping network speeds or forcing moode to receive parts of the tracks little by little so that I don't get this spike at the start ? I haven't found any options in my player to do so (Audirvana).