Strange sound if I turn off and turn on the prophet.

[Antonino]

If you turn your prophet off and on again after a few minutes, is the sound the same?
In my scratches increase, the sound becomes a little crap.
If I disconnect and reconnect a jack, sometimes the sound adjusts and returns to normal.
I have already replaced the main board and the panel boards, nothing changes, I just have to change the power supply.
I'm going crazy with this.