Hi all, I just bought a beautiful Allen & Heath Xone DB2 mixer second-hand and when connecting to my old NAD amp using XLR to RCA cables, there's a noise that comes and goes from the right channel and not the left. I tried swapping cables around and the fault seems to lie with the mixer itself. I would describe the noise as like a flickering flame that sometimes turns into a roaring fire and then gets stuck for a while before dying down again. It reminds me of the way my very unreliable Vox valve guitar amp sometimes sounds. I'm always prepared for a bit of static with audio equipment, but this noise is weirdly inconsistent and much louder than the regular hiss you'd expect to get. Does anyone have any thoughts on what could be causing this? Thanks!