orkney
Headphoneus Supremus
- Joined
- Jul 9, 2004
- Posts
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Hum in the signal/headphones or physical hum from the unit? If in the signal, I’d suspect tubes (but seems you’ve already tried different ones) or the source - is the hum still there with all RCA’s disconnected (pre-outs too, if any)?
Physical hum in the unit and in the signal -- dissipates after a period of time but this is new, since he's been using it happy for months without issues, suggesting it may be tube related.