Did you try the plug plugin with vlc and check in hw_params if the hw plug converts to mmap mode?
Apparently vlc has problems with stream timestamps reported by alsa, not with the actual streaming. Maybe in rw mode the I2S driver provides some wrong timestamps. Therefore I would try vlc -> some plugin allowing to go from RW to mmap -> i2s hw.
Apparently vlc has problems with stream timestamps reported by alsa, not with the actual streaming. Maybe in rw mode the I2S driver provides some wrong timestamps. Therefore I would try vlc -> some plugin allowing to go from RW to mmap -> i2s hw.
Do you mean this?
Code:
pcm.test {
type plug
slave {
pcm default
}
}
pcm.!default {
type hw
card E30
}
Code:
$ aplay -v -D test --period-size=1764 --buffer-size=131072 -r 44100 -c 2 -f S32_LE Music/sample-32-3.wav
Playing WAVE 'Music/sample-32-3.wav' : Signed 32 bit Little Endian, Rate 44100 Hz, Stereo
Plug PCM: Hardware PCM card 1 'E30' device 0 subdevice 0
Its setup is:
stream : PLAYBACK
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 44100
exact rate : 44100 (44100/1)
msbits : 32
buffer_size : 131072
period_size : 1764
period_time : 40000
tstamp_mode : NONE
tstamp_type : MONOTONIC
period_step : 1
avail_min : 1764
period_event : 0
start_threshold : 131072
stop_threshold : 131072
silence_threshold: 0
silence_size : 0
boundary : 1073741824
appl_ptr : 0
hw_ptr : 0
Code:
$ more /proc/asound/card1/pcm0p/sub0/hw_params
access: RW_INTERLEAVED
format: S32_LE
subformat: STD
channels: 2
rate: 44100 (44100/1)
period_size: 1764
buffer_size: 131072Now:
tstamp_mode : NONE
When everything works fine:
tstamp_mode : ENABLE
I'm not sure if it's related to issue though. Maybe that depends on the MMAP mode or it can be changed separately.
tstamp_mode : NONE
When everything works fine:
tstamp_mode : ENABLE
I'm not sure if it's related to issue though. Maybe that depends on the MMAP mode or it can be changed separately.
One more comment from the VLC forum:
If RW mode does not work properly, then that's a driver bug, though it's far from certain that that's the problem. There are no reasons for VLC to use MMAP mode ever.
If RW mode does not work properly, then that's a driver bug, though it's far from certain that that's the problem. There are no reasons for VLC to use MMAP mode ever.
Filed the bug report, hopefully in the right place:
Audio playback issues without PulseAudio * Issue #4563 * raspberrypi/linux * GitHub
Audio playback issues without PulseAudio * Issue #4563 * raspberrypi/linux * GitHub