It only started after I put a new chain on.
Doesn’t do it in the other two rings.
Does it mean the middle chainring needs replacing?
Seems a bit of a silly question seeing as it doesn’t happen in the other two but thought I’d check. My technical knowledge is a bit limited so grateful for any advice!
Cheers

I suspect the middle ring is worn and the chain isn’t sitting on it properly. What’s the cassette like?

Cassette looks ok. I think you’re right and it’s the chainring. Oh well, time to get the credit card out… 🙄
Thanks for reply.

Look at chainring teeth, if they’re hooked then definitely change, before the dreaded chain suck.

Might be a burr* on one of the middle chainring teeth – have a look and if there is file it smooth.

* Sometimes the chain wears a flat spot on the edge of the chainring teeth where it connects with the chain, and sometimes this flat spot (burr) grows/squishes outwards and becomes wide enough to catch on the side plates of the chain causing a “ping”. Soft chainrings are very susceptible and if ignored this can lead to chainsuck. Solution is to file off the burr.

This is really bad, but if it’s just on a couple of teeth a quick file will fix it.