Yes, I now reckon it was glue, as it is the same stuff around the other 2200 uF cap (6.3V). However the first 2200uF cap I removed (25V) did have a low 1650 uF capacity so it was deteriorating, and as said, it was running hot. The other cap I have not removed, but I will when I get the caps to replace them. I just hope this fixes the fault. Will come back again on progress! By the way, the "glue" was rock hard but bubbly looking. See photo above. I thought the repair might be an easy one, I now have doubts, and it will need more investigation.
UPDATE with the fault: Replaced the 2x electrolytics....made no difference. 🙁 tapping the board on one side caused the tuner to operate normally. Tried to narrow the fault by different tapping positions....not conclusive. Turned board over again and looked for dry joints or track faults. I " imagined" some soldering looked "iffy" but after resoldering made no difference. Further tapping went on until I tapped the small vertical heatsink on the regulator. This caused the fault to disappear long term. I soldered the 3x legs of the reg. and it still works OK. I don't know what the fault was, but it is all back together and sounding wonderful. For how long, only time will tell. 🙂
