First Look 48 Fosi Audio GR40: Airy Goodness

[@Fishio]

Regarding the “ground hum” that goes away when touching the device’s case, I had that happen with a different device before, and the issue ended up being that my headphones cable/connector was not fully seated into the device’s input jack. Also, if the issue goes away when the USB is disconnected, you might be able to fix it with a USB isolator. The JDS Labs Synapse fixed a ground loop issue I was having (just note that the max supported USB current is 100 mA).

[@thelastrhino2581]

To eliminate the case floating hum just power it with a grounded adapter or connect it via RCA out (even if not using them) to a grounded amp.

[@masterazlan6999]

Naa...my old skol mt604 with 4 pentodes way better noobs long time ago..Peace!