2009 R56 "Hi Temp" message on sound system - now dead?

[triang]

Weird one - 1 1/2 hours listening to Iphone on Aux.... This "Hi Temp" message appeared - radio and CD dead ...waited 20 minutes - stuill dead ...can hear Iphone but it's v quite so seems like sound system amp has blown a temp sensor.

But how can you rest it or does it mean new sound system needs fitting? (££££)

Also searched google and forums and although there were reported problems on BMWs too a) there was only 3 or 4 problems reported and b) no resolutions reported at all

There must be zillions of Minis and Beemers with the same (standard) sound system - can't believe I'm the only one to get this?

Any help, ideas etc gratefully received!