ca-810

Ok I re soldered the grounds and repaired a broken trace that one of the grounds was connected to and it greatly reduced the hum however there is still a hum that gets louder when the volume is turned up and when the subsonic filter is switched on.
 
Zero at minimum accept when you turn the subsonic filter on
Found the problem..
After much head scratching,cussing and kicking my dog I finally found a microscopic break in one of the traces on the main amp board.There are two jumper ground wires on the main amp so I decided to remove them and when I did the hum was greatly reduced so I followed the trace to a transistor and found the middle leg soldered to a pad that had the break in it.Fixed that and no more hum..
 
Ok got that fixed..Now when I power up I get a crackling noise from the left channel but after a minute or so it goes away???
 
Freeze spray came in the mail today and I found two bad 2sc1571 transistors they are intermittent.Anyone know a good replacement for these?
 
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