Loop Playback Bug

• Jan 17, 2023 - 07:40
Reported version
S3 - Major

Open any score, and select one bar. Click "Loop Playback" and see the two blue bars with arrows indicating the looped section. Hit play, and the score plays back NOT the selected, highlighted bar, but one a few bars previous.


I recall MuseScore 4.0 playing the wrong measures in Loop mode (an unhighlighted group of measures) but I don't know what triggered it. Didn't investigate because I found too many problems with looping and with 4.x in general.

If you encounter the Loop issue again tried to identify exact steps to replicate and report those here. I doubt I'll encounter the issue anytime soon because I'm really just using 4.x to see the direction it's heading. Currently it's far from a working environment for me.

Reported version 3.6 4.0

I don't encounter this problem in 4.01 under Linux, the two flags are respected to the letter.

Bug does happen for me in the attached score, which was originally created in MS 3.6, but now re-opened in MS4.

OS: Windows 10 Version 2009, Arch.: x86_64, MuseScore version (64-bit): 4.0.2-230651553, revision: dbe7c6d

Steps to reproduce:
* open score, switch to part "Tenor", select the measures of the last system (28-37), click the loop icon
* observe how the selected loop region is correctly displayed on screen:
MS4.0.2 loops wrong measures.png
* start playback

Expected behaviour: playback loops measures 28 - 37.
Observed behaviour: playback loops measures 12 - 22.

Attachment Size
El_Grillo_(The_Cricket) MS4.mscz 157.22 KB
Frequency Many Few
Status needs info active

As the issue tracker here on musescore.org is being discontinued, better report this on GitHub

In reply to by joghi1166

Problem probably is caused by missing synchronization between adding, appending or removing measures and loop playback. For example, start a score with 32 measures (number 1 - 32) and append 10 more (number 33 - 42) at the end. If I try to do loop playback on measures 34 - 37, it loops between measures 2 - 6. 2 is exactly the offset of the loop start counted from the first appended measure, and 6 is exactly this offset of the loop end. I verified this faulty behaviour with some other measures ranges, too.

Reproducibility Randomly Always
Severity S3 - Major S2 - Critical
Type Functional Performance

Started happening with mine today. Added measures and set repeats. playback starts in the wrong location, and skips all added measures. Solution: take out repeats. It work correctly.