So at first i really loved Esbern, he had a voice that sounded like my grandfather.

Then when we got to that temple place thingy, i noticed he started changing voice actor (along with accent..) every 2 lines.. and it REALLY bugged me!

Did anyone else notice this?

Must be a bug in your game... He didn't change voice for me..
He still sounds like Max von Sydow

I noticed that too, there is a very noticeable change of voice actor. It happened to me when back in Delphine's underground hideout in Riverwood.

Have seen threads on the same topic in the past, its either you guys' game are bugged or I'm too deaf to notice the difference D:

It's the 2nd one. There are bugs affecting Esbern's dialogue, but some of his lines do indeed appear to have been recorded by a different actor. I'd assume they wrote extra lines after Max von Sydow had already done his recording session and scheduling/costs meant they couldn't get him back to do the rest.

This must be it cause they are defenetly Esberns lines but he gets another voice (which is still exclusive to him) and sounds a little drunk(or isirsh?) cause he sludders with his 2nd voice.

Makes sense, I will pay more attention to his dialogue in my 2nd play through

You're hearing things.

Did you take an arrow to the knee or something?

Yeah I noticed it in Delphine's room once we returned from Riften, I thought I might have just been hearing things, good to know other's heard it too. He sounded like he had a weird german-ish accent from what I can remember and it was really noticeable when he reverted back to his normal voice.

Maybe this is like a Martin Septim or Jauffre thing, where there were 2 voice actors, and you are accidently getting the non-canon one?