SC10 4x4 stock Esc?

[ClydeBuilt]

My esc seems to have given up the ghost, despite a pretty short running life!

It does power up...sorta?
But it wont go through its little music routine it does at startup, so I cant change any other settings. It still supplies power to the RX as the steerings fine. The fan runs too.

Is this a common fault, or is it a p.o.c. to start with?

If thats the case, can anyone recommend a reasonably priced solution?
Im looking at stuff on HobbyKing and the original is on offer there.
So do I replace the stock, upgrade to higher amp but still pretty cheap, or sell my son and the dog and get something else?