Created attachment 173363 [details]
5-second frame counter

SUMMARY
In the 24.* versions it seems to me that playing or editing MPEG files under Kdenlive has become more unreliable. At least under 23.08.5 (Qt5) I didn't notice frozen frames when moving the playhead back/forward. They become more noticeable when you cut such a clip in two and quickly go back/forward a frame with the < and > keys near the cut.

STEPS TO REPRODUCE
1. Open the video attached here, a 5-second clip produced by Kdenlive using the time frame counter tool;
2. In the timeline go fast forward a few seconds with the ">" key, then back to the beginning of the clip using "<"
3. Make a cut somewhere e.x. in the middle

OBSERVED RESULT
Kdenlive manages to play the video, it stops to do so for too many frames when going backwards with the mouse or the "<" key. This makes it impossible to do accurate cuts scene by scene, because you don't know at which exact frame the cut is really happening.

EXPECTED RESULT
I tried playing/editing the same MPEG video under Kdenlive 23.08.5, and there I don't see the issue with the playback/jumping frames. 

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: 
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION