I recently bought a Marshall DSL20HR head and a Marshall 1936 Lead 2x12 cab.
The head has a cab emulator out, so I hooked it up to my audio interface and was playing through my pc monitors. I turned up the volume and gain on the ultra gain channel and a strange buzz/noise came from the head when I would strum a chord or pick a note.
I only noticed this because I had the level on my interface low as I was just testing the cab emulator out. I have alos tested this with the head not plugged into either my interface or the cab and still get a strange noise/buzz.
As this is my first valve head I'm not sure if this is just something that happens when you turn up the volume and gain - as the amp is being pushed harder, or if there is a fault with the head and I need to take it back to the shop I purchased it from.
I will link below some video of the problem. The first video sounds worse than it is as I put my phone directly on top of the head as I play. It's not the signal noise from the amp that I am worried about, it's the rattle when I strum chords or hit notes...
Any help would be greatly appreciated, I'm probably just over reacting, but it would be good to get some reassurance.
From the recording on youtube it is very difficult to hear any problems, if you are worried as you have just purchased the unit we would recommend that you have the dealer check it over for you to make sure it is working correctly.