It seems like SoundTouch refuses to time-stretch samples with a sample rate higher than 192 kHz. For the time being you can circumvent this issue by first downsampling the sample to 192 kHz or lower.

The issue will be fixed of course, I'm just not sure yet how exactly, as time-stretching has some time-sensitive parameters (no surprise hopefully) and simply pretending that the sample has a lower sample rate will mess up those parameters.

Instead of crashing, a warning is now shown. Not optimal, but it's the easiest we can do for now. You can either get a new build from https://builds.openmpt.org/builds/ (r11711 or later) within a few hours or change the update source in OpenMPT's settings to "Next" rather than "Release" to receive an update (1.28.05.02).

Goody good. Works without crashing and I get the error message "sample rate must be 192,000 or lower"