Leak Delta 70 - No Sound/Buzzing


I currently have a Leak Delta 70 which doesn't seem to be working. Whenever I try to play anything, all that comes out the speakers is a buzzing sound on both channels. The buzzing is present no matter which input I use and gets louder when I increase the volume.

I have a basic understanding of electronics, however I can't seem to be able to figure out where the problem is coming from.

Any help would be much appreciated.