Swampwalker,
I had the same problem. It was DC on the line. I fixed it with a combination of the 'Ah! AC Offset Killer' and an isolation transformer. The 'Ah! AC Offset Killer' seemed to be 90% of the cure.
Now there is just a teeny hum that you have to listen very carefully to hear. I mentioned this fix to Mick soon after I got my Supratek and he said he would look into it. Not sure what happened after that.
I had the same problem. It was DC on the line. I fixed it with a combination of the 'Ah! AC Offset Killer' and an isolation transformer. The 'Ah! AC Offset Killer' seemed to be 90% of the cure.
Now there is just a teeny hum that you have to listen very carefully to hear. I mentioned this fix to Mick soon after I got my Supratek and he said he would look into it. Not sure what happened after that.