Transformer bubbling

I've built an ecl86 amp based on the babyhuey design. The amp has been running extremley hot after half hour. The area around the valves are untouchable without burn pains - as is the power transformer and also the components which are all soldered close to the valve pins.

I seem to remember the power transformer leaking wax before I salvaged it from an old heathkit amp.

I switched it on today and as soon as the HT came up (gz34) - I started to hear an awful squeal through the speakers followed by a bubbling sound from the amp.

Is this my transformer?

Could this have been made worse by using a bleed resistor that is too small (33K)?

cheers Stuart