Sound garbled after DVD play

I have one annoying issue with my WD TV Life.
If I play an mp4 video the sound is garbled - similar to an old radio with bad reception - but only when I played a DVD iso file before. Turning on and off the device fixes the problem, so it is not a big deal, but it is still annoying.

Anybody  encountered that problem before and found a solution? I do run the latest version of the firmware.

Have you tried a reset to factory defaults?

yup - tried that.

But I am curious to learn if this only happening to me.

Can you play a DVD (from a folder or iso file) and then after that play an mp4 file and the sound is good?

Thanks,

Merlin