track slows down in case of buffer underflows

Bug #1198306 reported by Daniel Schürmann
This bug affects 2 people
Affects Status Importance Assigned to Milestone

Bug Description

On aggressife latency settings, underflows may happen in unexpected bussy situations.
Wgile this is already a bad situation things are getting worth due to the fact that Mixxx tryes to repeat the missed frames.
Effectifely the track slows down what effect a dancing crowed more than a dropout of a few miliseconds.

Is a fix to this bug possible included in our master sync aproach?

Revision history for this message
Owen Williams (ywwg) wrote :

I wouldn't count on master sync to fix this issue. If the master were set to internal it might be possible that the other tracks would catch up, but in general master sync is about setting relative rates, not enforcing an atomic clock.

Revision history for this message
RJ Skerry-Ryan (rryan) wrote :

I don't believe we try to repeat missed frames. We respond to each callback with no regard to how long it took us so there is no repetition... just late delivery.

Revision history for this message
Daniel Schürmann (daschuer) wrote :

Yes, exactly this is the issue. Maybe repeat it the wrong word here. When an underflow happens I think the sound card plays the samples that are in the its ring buffer from the last call. The intended samples are just shifted to the next round.
This late delivery leads to a notable speed change of the track.

A solution for this bug will drop the samples outdated samples and continues with the right samples as if there was not underflow.
We need a micro seek for all decks or something.

RJ Skerry-Ryan (rryan)
Changed in mixxx:
importance: Undecided → Low
importance: Low → High
status: New → Triaged
Revision history for this message
Daniel Schürmann (daschuer) wrote :
Revision history for this message
Swiftb0y (swiftb0y) wrote :

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:

lock status: Metadata changes locked and limited to project staff
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