phono section noise

i have a problem with my phono section on my melos 333 gold, they are out of business so i have no where to get it fixed. i have a bad wind noise coming from the left channel. i have already replaced the tubes. there was no improvement. i have an electronics wizard friend and he touched up all the ground connections and solder connections he didn't think looked so good then he tested the caps and resistors with an LCR meter and a $40,000 oscilloscope he brought over. didn't really find anything wrong during the testing. just the touched up connections was all we did. i hooked it back up and i thought it was fixed. the wind noise went away, but it turns out only for about two weeks, now its back. can anyone give me any ideas for what to test or look for? it would be appreciated. thanks