I am running Debian Buster(10) 64-bit with the latest buster-backports v5.9 vanilla and PREEMPT_RT kernels playing out to a USB DAC via ALSA hw direct.
When I run 2 channel content (no convolution), it plays fine. When I run 2 channels with convolution (@ 74X realtime), I get random pops/clicks on manual start of a track or when I switch tracks. If one song ends and the next starts in sequence, the start of the next track does not appear to have the startup pops/clicks. It appears to only happen on manual track selection or selecting "NEXT TRACK".
I have tried:
- different ALSA buffer sizes (larger and smaller)
- more or less taps
- more or less sample rates [44.1-384]
- more or less FIR sample rates [44.1-384]
- no resample and resample to fixed output
- no SOX and SOX
- vanilla and RT kernels
- disabled background library searches
- disabled DLNA server
- enable/disable play silence before tracks
- with and without track decoded memory playback
- lightweight desktop and display manager
- blacklisting onboard audio snd_hda_intel
I have also tried using the Redhat "tuned-adm" package to try different performance profiles, still same behavior.
The PC is an IvyBride i7-3770K with 16GB of DDR3 memory.
Htop shows an average CPU load of [0.5-0.7]% of the 4 cores/8 threads and no swap space being used.
Htop's tree view shows [6-8] mediacenter26 threads.
Any ideas on how to get rid of the random pops/clicks on manual track startup ?
Thanks much.
alsacap
*** Scanning for playback devices ***
Card 0, ID `Interface', name `32bit 384kHz DSD Interface'
Device 0, ID `USB Audio', name `USB Audio', 1 subdevices (1 available)
2 channels, sampling rates 32000, 44100, 48000, 88200, 96000, 176400, 192000, 352800, 384000 Hz
Sample formats: S32_LE
Subdevice 0, name `subdevice #0'
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Topic: Pops/Clicks on track startup with Convolution (Read 1969 times)