View Issue Details

IDCategoryLast Update
0006254bugs2020-03-27 21:54
ReporterchaotAssigned To 
Status closedResolutionfixed 
Product Version4.0-rc 
Fixed in Version 
Summary0006254: Shuttle speed control has massive lags
DescriptionArdour Version:
Ardour 4.0.rc3.21

Linux Mint 17, 64 bit

When scrolling with the shuttle speed control it is extremely laggy. Strangely this only seems to happen, if a MIDI track is present in the session. See attached video for clarification.

- Open new session
- Add MIDI track
- Scroll with shuttle speed control

Always reproducible with my current setting but I don't know of someone else experiencing this issue.
TagsNo tags attached.


related to 0006247 confirmed Shuttle (sprung) when in stop mode always returns to zero 
related to 0006248 new Shuttle (sprung) sometimes continues to play when released 


2015-04-15 14:55


out-1_short.ogv (4,254,841 bytes)


2017-05-26 12:51

reporter   ~0019743

This is still present in 5.8. Still, only after having added a MIDI track.


2017-05-26 14:01

administrator   ~0019744

It depends a lot on the buffersize. Speed-changes happen once per process-cycle.

Particularly mouse-wheel'ing on the shuttle can queue a lot of GUI events which are processed at a lower rate if the buffersize is not small.


2017-05-26 17:28

reporter   ~0019745

Last edited: 2017-05-26 17:29

View 2 revisions

Indeed, if I decrease the buffer size a lot then this behavior is gone.

I'm not familiar with this part of the code base of Ardour. Would it be possible to drop certain GUI events if we know that they will become obsolete because of a later event in the queue?

Just to also make this clear: I don't care about the shuttle control because I would never use it productively in any way. I just think that if it exists, it shouldn't be buggy.


2020-03-27 21:54

reporter   ~0021059

This is not an issue anymore as the shuttle control changed significantly since the last comment.

Issue History

Date Modified Username Field Change
2015-04-15 14:55 chaot New Issue
2015-04-15 14:55 chaot File Added: out-1_short.ogv
2015-04-16 04:52 x42 Relationship added related to 0006247
2015-04-16 04:53 x42 Relationship added related to 0006248
2017-05-26 12:51 chaot Note Added: 0019743
2017-05-26 14:01 x42 Note Added: 0019744
2017-05-26 17:28 chaot Note Added: 0019745
2017-05-26 17:29 chaot Note Edited: 0019745 View Revisions
2020-03-27 21:54 chaot Status new => closed
2020-03-27 21:54 chaot Resolution open => fixed
2020-03-27 21:54 chaot Note Added: 0021059