Thanks DT for the reply!
And thanks for the tip about finding IG00151, i hope i'll find some economic solutions when (and if) i'll face these non-working chips ..
I know the wonderful and useful Old Crow's website, but actually i also couldn't find anything about the rebuilding of certain IC. Fingers crossed!
I understand very well the nightmare you have experienced in the studio ... As you say, it is precisely to avoid these things that we try to revise these instrument.
Then i think that even a minimum of luck maybe doesn't hurt... (i know that this sentence has little to do with electronics works ;))