automatically attempt to use ALSA plughw devices if unable to open hw device
Bug #1475420 reported by
Be
This bug affects 1 person
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Mixxx |
Confirmed
|
Wishlist
|
Unassigned |
Bug Description
Users often run into errors with PortAudio being unable to open their sound card because the sample rate is not supported. The workaround for this is to set the PA_ALSA_PLUGHW environment variable to 1 before starting Mixxx. It would be helpful if users did not have to do this and this was handled automatically. Should this be changed in Mixxx or upstream in PortAudio?
description: | updated |
Changed in mixxx: | |
importance: | Undecided → Wishlist |
status: | New → Confirmed |
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Since PA_ALSA_PLUGHW is an Portaudio flag, it is up to Mixxx to set it.
But we need to careful consider when Mixxx should set this flag. I think it should be the last resort, since it adds another re-sampling stage to the audio processing chain.
Every resample stage adds noise to the stream, since it tries to predict the voltage level between to samples.
If you set Mixxx to a native soundcard sample rate it is able to process the Audio with only one resampling stage. We pass the samples with the source sample rate to the Enginebuffer and re-sample it in one step to the output sample rate, including all scratching and pitch shifting: /github. com/mixxxdj/ mixxx/blob/ 752b3cc3f64c359 7b78a5818b3533a 1ec82d5f26/ src/engine/ enginebuffer. cpp#L981
https:/
The only case I can think of that requires an additional re-sampling is if two soundcards have no common native sample-rates.
But I have not heard of a sound-card that does not support 48 Khz. Is there any?
If yes, Mixxx may detect it and guide the user to the best set up.