Took the case off my old Denon unit to give it a bit of a clean, and noticed this.

Looks like some sort of meltdown event to me?

Anyone know what it is? And should I worry about it? Or put the lid back on and pretend I haven’t seen it?

Cheers!

Just glue to help secure/support things.

That’s the nuclear core. It will be fine as long as it doesn’t warm to above 25 degrees C . . . . .

Flux capacitor.

Don’t travel faster than 88 mph.

(It’s glue. And a lot of dust/dirt)

Jeez, where have you been keeping that amp?

Probably due a proper clean and a swap out of old electrolytic capacitors and maybe treat it to some nice new potentiometers!

Jeez, where have you been keeping that amp?

Underneath a lazy and fluffy moggy, mostly. He loves it there. You should’ve seen it before I hoovered it.

Thrunge isolation foam.

I do love this forum.

Looks like someone left a pack of Grandad’s butter candy on top of your Denon.

That looks like the glue used to hold the coils in place. Possibly the transformer has overheated or being running very hot for a while, or the whole thing has been put somewhere where it has go too hot.

The leakage of the glue in itself isn’t an issue as it’s non conducting and just makes a mess.

It does suggest you might have an overheating problem…

It does suggest you might have an overheating problem…

Due to the moggy lying on top of the vents?

“this” is a bit vague OP, there are many things in your photo including the glue 😉

As above could be it got a bit hot, does the fan run ? Is there dust blocking the vents ?

For the avoidance of doubt I am not an electronics person but it’s STW right so I can comment (note I did build a computer in 1977 … at my age I don’t remember much though ;))