Afternoon gents.

Just retubed my Carvin Legacy. Well, thanks to a ballsup from the delivery guy I only got 4 preamp valves instead of 5. So I just left in the older reverb valve and replaced the others (3 for the preamp and 1 for the 'power diver', whatever that is).

And now it just won't make any sound. It played perfect for about half an hour, and then there was a pop and it cut off.

At first I thought I might've accidentally nudged a power valve out, but they're all firmly stuck in and glowing as normal. All the preamp valves are in properly and glowing. All the wiring looks normal, and the cab is connected up right. Speaker cable and guitar cable are fine.

I have a niggling feeling that the power valves are just slowly dying, but is there anything else that it could be?
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