Hi,
I don't know if this might be related to some software update. From time to time I get a distorted / crackling sound when listening to youtube videos via ALSA-> loop-> Jack. With just Jack everything is fine. Anyone else observed this recently?
Distorted / Crackling Sound via ALSA -> Loop -> Jack
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- lilith
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Re: Distorted / Crackling Sound via ALSA -> Loop -> Jack
It happens also with 512 or 1024. When listening to a sinusoidal tone and the problem is present it sounds as there are some higher harmonics overlaying the root tone.
Re: Distorted / Crackling Sound via ALSA -> Loop -> Jack
This sounds similar to the issues I had with my old Tascam US 122 mkII.
Every 10 minutes or so there were ugly noises and harmonics on top of the audio signal which were persistent until I unplugged the interface.
It was a hardware issue though. Both on Windows and Linux the drivers / firmware seemed to be a little buggy.
Every 10 minutes or so there were ugly noises and harmonics on top of the audio signal which were persistent until I unplugged the interface.
It was a hardware issue though. Both on Windows and Linux the drivers / firmware seemed to be a little buggy.
- lilith
- Established Member
- Posts: 1698
- Joined: Fri May 27, 2016 11:41 pm
- Location: bLACK fOREST
- Has thanked: 117 times
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Re: Distorted / Crackling Sound via ALSA -> Loop -> Jack
I tried a different interface and I also get the crackling in firefox via youtube. It seems only to happen with the alsa -> loop -> jack bridge. Is there anything that I can test to localize the reason for this? Are the values in alsa config file relevant? My interface works best with 48kHz (which is also set in cadence).
Code: Select all
cat ~/.asoundrc
# ------------------------------------------------------
# Custom asoundrc file for use with snd-aloop and JACK
#
# use it like this:
# env JACK_SAMPLE_RATE=44100 JACK_PERIOD_SIZE=1024 alsa_in (...)
#
# ------------------------------------------------------
# playback device
pcm.aloopPlayback {
type dmix
ipc_key 1
ipc_key_add_uid true
slave {
pcm "hw:Loopback,0,0"
format S32_LE
rate {
@func igetenv
vars [ JACK_SAMPLE_RATE ]
default 44100
}
period_size {
@func igetenv
vars [ JACK_PERIOD_SIZE ]
default 1024
}
buffer_size 4096
}
}
# capture device
pcm.aloopCapture {
type dsnoop
ipc_key 2
ipc_key_add_uid true
slave {
pcm "hw:Loopback,0,1"
format S32_LE
rate {
@func igetenv
vars [ JACK_SAMPLE_RATE ]
default 44100
}
period_size {
@func igetenv
vars [ JACK_PERIOD_SIZE ]
default 1024
}
buffer_size 4096
}
}
# duplex device
pcm.aloopDuplex {
type asym
playback.pcm "aloopPlayback"
capture.pcm "aloopCapture"
}
# ------------------------------------------------------
# default device
pcm.!default {
type plug
slave.pcm "aloopDuplex"
}
# ------------------------------------------------------
# alsa_in -j alsa_in -dcloop -q 1
pcm.cloop {
type dsnoop
ipc_key 3
ipc_key_add_uid true
slave {
pcm "hw:Loopback,1,0"
channels 2
format S32_LE
rate {
@func igetenv
vars [ JACK_SAMPLE_RATE ]
default 44100
}
period_size {
@func igetenv
vars [ JACK_PERIOD_SIZE ]
default 1024
}
buffer_size 32768
}
}
# ------------------------------------------------------
# alsa_out -j alsa_out -dploop -q 1
pcm.ploop {
type plug
slave.pcm "hw:Loopback,1,1"
}