Bug 449700

SUMMARY
**
When previewing  timeline, playback pauses briefly at each new clip
***

As Play-head passes each clip on the timeline, playback on the project monitor briefly pauses. This also occurs during a dissolve/wipe transition. This does not happen with previous version before 21.12.0.  Occurs with both Appimage and Flatpak. Video clips used in project are 1080p/ 50 fps/ .mts 

STEPS TO REPRODUCE
1. Load a project
2. Play through timeline until clip changes
3. Also occurs when clips have been added to a new project

OBSERVED RESULT

Preview plays smoothly until next clip or transition in timeline is reached, play back pauses briefly ( <1s) . Playback sometimes continues to play back at a low frame rate

EXPECTED RESULT

Smoothly cut or transition to next clip and continue to play smoothly.

SOFTWARE/OS VERSIONS

Linux:  Kubuntu 21.10/KDE Plasma: 
(available in About System)
KDE Plasma Version:  5.22.5
KDE Frameworks Version: 5.86.0
Kernel version: 5.13.0-28-generic
Qt Version: 5.15.2

ADDITIONAL INFORMATION

Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-4790K CPU @ 4.00GHz
Memory: 23.4 GiB of RAM
Graphics Processor: NVIDIA GeForce GTX 750 Ti/PCIe/SSE2