Venue DI problem - hum and popping mute button from grounding issue?

[Caleb_Elling]

Hey Seth,
I got your email earlier, and I sent you a reply.

If you get back to me at your convenience, we should be able to get this figured out for you.

[Sethdw]

Hi I've had a venue di for a long time but I've never used it on stage because it has quite a grounding hum whether it is powered by 9volt or grounded power source. On top of that it makes a terrible popping sound when I mute it to tune, and if I accidentally bump it it makes a banging noise as if it where a raw ontact pickup. Any ideas, suggestions on where to get it work on, or how much it might cost out of warrantee?