Problems with biasing my MM hd130

I have a mm hd130 with solidstate driver and for a while ago I was going to put a new set of tubes in it.
And one of the tubes had a short circuit between grid 2 and grid 1 so the amp sounded like "oouuii" and started to smoke.
So then i changed the resistor that smoked wich was a 220 ohm resistor r55 or r57 and put the old set of tubes in it.
and when i was trying to measure the bias across the 3.9 ohms and i got about 6 mV and the bias pot doesn't change the value more than a few mV.
do anyone have any tips about something i could try out?

First thing I would try is another set of tubes. It sounds like they are not conducting the gazinta properly(technical term-don't try this at home!) Sorry-couldn't resist. Anyway, I'd try the tubes FIRST, then check the cathode current. After that, the cathode driver circuit MIGHT be suspect. Then I'd look at the drivers. Mike.