No guitar sound from amp

[KPA]

Would anybody here know what’s wrong with my amp (Peavey Bandit 112)? It’s making noises when it's switched on and when I tap it, so it definitely ‘works’, but absolutely nothing coming from the guitar when it's plugged in. I’ve played the guitar through a different amp and it works fine so it’s not the guitar or the lead, so I’m at a loss (I'm definitely not technically-minded). I’ve been online but I don’t really know what I’m looking for or how to describe the issue.

[Pappy B]

If you haven't done so already, use some contact cleaner on all the jacks, switches, pots and connectors. You can also try using a a patch cord from pre-amp out to power amp in. If this helps it's a sure sign that it's time to do some cleaning.