folks.
Heater cap was looking a bit ugly so i took it off and polished it up. After putting it back on my SEX developed humming (louder on the left channel but present in both).
Followed the manual and did resistance checks. Passed all checks. Then I did a voltage test and found a damaged sparky wire. Replaced it and got a pass on the voltage test. Lastly did a c4s voltsges test and it passes just fine.
Replaced the pot with an identical a100k from my crack kit thats waiting to be built. I am using a different power cord and my outlets are grounded.
When i checked the rca jack i noticed that the humming is magnified when rca cables are plugged in while connected to a source. Tried replacing the rca cables. Still hums. Used my phone as a source. Still hums.
Did some futher testing and desoldered the rca jacks and tested the leads. Shorting the rca leads together doesnt produce hum. Putting the positive peg or negative part of the rca cable on the solid blue cat6 cable produces a hum but not one the white blue lead. Same for the solid orange (but again to a much lesser effect) vs the white orange lead.
Any ideas as to what I screwed up?
Tonight I'll do the resistance and voltage check and post values. I am at work. However I have no issues passing the tests even after multiple checks.
Also double checked that the power transformer threads and spacers are setup right and tight.