So I've had my Marshall DSL 15H since late September and about a week ago when I was playing I heard a sound which I can only describe as a 'Pop!' and it started to fuzz a little every so often. I decided it'd be best if I switched it off. Came back to it 2 days later totally forgetting the incident and switched it on waiting for it to heat up for 5-10mins as I always do before playing, but within a minute of it being on while I was waiting for it to heat up, the fuzz began again. It's not fuzzing much but starts to act up more when I start playing.

Spoke to a lad at work who recommended that I take all of the tubes out, make sure they're not dusty and put them back in. So I did this but it hasn't made a difference.
I've seen some videos on Youtube telling you to tap the tubes with a pencil after its been powered on and heated up and it should be obvious to tell which tube is acting up, but its not.

Any advise?! Maybe its not actually the tubes? I've only had it since September so if I took it back to the guitar store would they just laugh?

If a fuse has blown it's most likely a power tube that's died.
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one of your tubes was probably crap to begin with, sadly that happens. they can go 5 minutes after you turn the amp on.

dont get tubes until you get a new fuse in it first.
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it does sounds like a fuse but the problem is that it blew for a reason so if you put a new fuse in it will probably go again.

sounds like a tube issue but something is getting squirly. there are always anomolies, dont worry if they "laugh" at you at the store. you paid for an item, it is under warranty
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