View Issue Details

IDCategoryLast Update
0008365bugs2020-11-21 20:10
ReporterunfaAssigned To 
Reproducibilityrandom 
Status newResolutionopen 
PlatformArchOSLinuxOS Version(any)
Product Version6.2 
Fixed in Version 
Summary0008365: Randomly introduced latency
DescriptionI'm using Ardour 6.2.43 (rev 6.2-43-g15fcb5c782) - I've recently noticed random latency problems on certain tracks. Suddenly my drums or bass synth would start lagging behind the click track by 0000071:0000060 ms.
At first I thought it's a problem with some plug-ins I'm using, I suspected LSP, as I've used them a lot in the affected project.

But then it happened after I added submix bus to a Black Pearl Drumkit (Multi).
The MIDI track was fed into multiple audio buses. These also send signal to 2 Reverb Buses in varying amounts.
When I've created another bus and routed all the individual channel buses to it - the whole drum line started to noticeably lag behind the rest of the track (quite a surreal sound).

Because of that I started suspecting that the problem might be caused by Ardour itself. Also - I'm not really using any plug-ins that I haven't been using in previously and I've never had such random latency introduced.

If I manually set the latency of my instrument plug-ins - it lets me compensate for it, but then the unexpected latency randomly goes away and my tracks start to rush instead of lagging.

After reloading the session - the latency problems seem to be gone, but re-appear randomly at times.

Here's a video I've quickly made to demonstrate the problem:
https://youtu.be/bWOSsuEyW0o

Can anyone reproduce this?
Tagslatency

Relationships

related to 0008472 new Newly added audio tracks are not correctly compensated for latency until Ardour session is reloaded 

Activities

soundguy30

2020-10-27 08:30

reporter   ~0025163

Does it still happen when using jack or ALSA

x42

2020-10-28 16:50

administrator   ~0025178

Preferences > Appearance > Toolbar > Display Latency Compensation Info

Does the I/O Latency show "ambiguous latency"?

unfa

2020-10-28 17:43

reporter   ~0025180

I'm gonna check when I encounter this again.

janisl

2020-11-06 08:17

reporter   ~0025202

I have this problem all the time now. And from what I have observed it applies to all newly added tracks and buses. And the only solution is to reload the project. And doing it every time I add new track is very anoying.

x42

2020-11-06 09:59

administrator   ~0025203

@janisl This sounds like an issue with JACK2. Does using Ardour/ALSA (no JACK) help? Is this with Ardout 6.3.0 ?

janisl

2020-11-06 12:31

reporter   ~0025205

@x42 Yes, with ALSA it works fine. It's 6.3.0.

x42

2020-11-09 17:14

administrator   ~0025210

> After reloading the session - the latency problems seem to be gone, but re-appear randomly at times.

Could it be that you have changed jack's buffersize while Ardour is running? and from then on there were inconsistencies (existing tracks newly created ones)?

janisl

2020-11-11 14:53

reporter   ~0025214

I don't change buffer size, and I can reproduce this every time.

Issue History

Date Modified Username Field Change
2020-08-17 19:23 unfa New Issue
2020-08-17 19:23 unfa Tag Attached: latency
2020-10-27 08:30 soundguy30 Note Added: 0025163
2020-10-28 16:50 x42 Note Added: 0025178
2020-10-28 17:43 unfa Note Added: 0025180
2020-11-06 08:17 janisl Note Added: 0025202
2020-11-06 09:59 x42 Note Added: 0025203
2020-11-06 12:31 janisl Note Added: 0025205
2020-11-09 17:14 x42 Note Added: 0025210
2020-11-11 14:53 janisl Note Added: 0025214
2020-11-21 20:10 x42 Relationship added related to 0008472