Mmi sound freezing

[Jepor]

Hey all 

Have an annoying issue , my mmi sound stops working from time to time , i have to turn off car and unplug the leads from the amplifier in the boot for around 10 min and then reconnect and it works again . Has anybody else has this issue  , is there a better way to fix this without having to unplug everything ? 

 turning mmi off and on doesn't work . 

 

Thanks