What is your operating system?
What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
Can you repeat the problem? If so, what are the steps?
(Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)
I remember one old version (many, many months ago) where there was a problem with waveform audio thumbnails update. It looks like that the problem returned. I’m cutting tracks into smaller pieces (and I don’t do anything more) and… after cutting quite often waveform thumbnail doesn’t correspond to the correct one. I have to click on More/Rebuild audiowaveform.
I have two filters for audio tracks (not sure if it’s important here): 1) Bass and Treble 2) Normalise: Two Pass.