RA180 lights go off, amp keeps working

H All,

I have been using a RA180 where we had some issues in the middle of the operation with all the lights suddenly turning off (and the VUmeters also not functioning) - the amp basically looks like its OFF - while the amp is still working (volume knob works).

I use the amp quite a lot (commercial listening bar in Oceanside California) and it is linked via a LIne-in to a MasterSounds mixer. I have the feeling this issue on the amp is created when for some time we play high output volume on the mixer. Does this make sense to you? It looks like a safety mode on the amplifier, but everything still keeps working…

I just want to avoid the amp dies suddenly one day.

Set-up - it sounds wonderful!
Technics SL1200GR
Mastersounds Valve mk2 (record out connected to Rose Line in)
Rose RA180 (internal crossover activated on lowest frequency)
JBL 4350A