Strange Mother-32 behaviour after leaving it on for a while

This has happened to me 3 times over the last 3 days, after leaving the device on for a few hours.

Firmware is 2.0, and I am playing from MIDI from Bitwig Studio. The Mother-32 is playing something very simple like this https://soundcloud.com/giacecco/right (forgive the effects, I forgot to remove them before bouncing). Then, I playback again, and it sounds like this https://soundcloud.com/giacecco/wrong instead. Of course I haven’t changed anything from before.

The device is set like this, nothing extraordinary https://imgur.com/a/e7tYGIk.

Turning off and on again the device fixes it. Any advice? Is the device broken?

G.