Chain jumping on the two smallest cogs on the cassette.

New chain, new chain rings, cassette is 2 months old. It’s indexed really well and doesn’t jump at all on the other 6 cogs. I am using an 11-speed chain on an 8-speed cassette, but this has never been an issue before. But I am open to hearing that running an 11-speed chain on an 8-speed cassette is a bad idea! Chain line isn’t perfect, but it actually favours the smaller cogs.

Any idea I would be super grateful. Thanks!

[Pictures of drive train](https://imgur.com/a/0G7mQke)