What's happening, is the THERMAL light is coming on FROM STARTUP... as in, when the h/u sends signal via the remote wire, the THERMAL indicator is showing and the amp is doing... well... nothing

So... I have checked all the obvious signs, the amp is receiving plenty of juice, around 13.8v (at idle), RCA's and speaker wires show no sign of shorting when checked with an ohm meter, and remote wire is also showing a healthy signal.
So wtf is happening???? Bung amp??? It's still under warranty so do we think I should be chasing it up?
Thanks,
Richard.