I got a Vox Valvetronix AD30VT-XL in October, it worked fine to begin with but in the last couple of months it has started to play up. It has started to switch into Delay mode on its own alot. Also, I changed the model over once and it started to make a huge screeching noise, everything was plugged in fine and the guitar strings were still. It's starting to worry me lately

Luckily, the amp has a one year warranty, so I can send it back if I need to. Has anyone experienced this with an XL series amp, and should I get anything done about it?
I love Vox. Don't get me wrong.
But you also have to remember, the digital age is here.
And Digital amps can become very defective.
Vox is notorious for it, same as Line 6.

You might need to swap it out for a new.
If the delay is turning on by itself and stuff.
It's probably an issue with the digital stuff inside.
Yeah sometimes my digital pedal does that. When I plug it in sometimes it will make this horrible static shreeking metallic vomit sound until I unplug it and plug it back in. Nothing is wrong with it.. just has always done that every once in awhile.
None are more hopelessly enslaved than those who falsely believe they are free.
The Valvetronix amps don't exactly have a good reputation for reliability. Power amp problems seem to plague them the most, but there are a few reports of delay related problems.

I thought mine sounded fantastic for what it was, but I couldn't live with an amp that needed to be in the shop once a month.
ESP LTD EC-256 and a Fender Deluxe VM
if it was a tube amp, I would normally say give it some time, maybe just a simple tube problem. With a digital amp, as soon as some weird glitch like that happens, I would return it ASAP for a new one under warranty.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
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