Because rarely used (and I am no collector), I want to sell my Grado HF-2 limited #2XX in original box with number and signature of John Grado. I am the first user.
The headphones are in "like new" conditions, how I got them.
sounds like an earth loop.
Removing an earth connection on DAC or source might work.
On my Yamamoto I recognized that some RCA plugs do not connect fine.
Try some other RCA cable.....
Private messages replied.
Some interest - no deal until now.
Remember that the D10 + opamp kit + Topkits opamps + Blackgate caps is a value of appr. 400 USD.
And it comes in mint conditions with a new original battery.