I had a similar problem with a 5si and a Squeezebox. The grounding cable as described here fixed the problem for me.
When I added my Eversolo DMP-A6, which is properly earthed, I no longer needed the cable.
I had a similar problem with a 5si and a Squeezebox. The grounding cable as described here fixed the problem for me.
When I added my Eversolo DMP-A6, which is properly earthed, I no longer needed the cable.