Single Player problem (offline)

I've been playing offline with the Annihilus client, waiting for March to finally arrive so I can return to no-lifing this server everyday....

But I have an FPS problem with offline gameplay.

Using the same graphics and testing online in a public game I have 100+ FPS, but as soon as I change to offline I am stuck at 25.

I've restarted pc, played around with graphic settings, re-launched the game, tried new characters, traveled to new maps, still stuck at 25-30 FPS.

When I pause and un-pause the game I briefly have 70+ then it goes back to 25 exactly.

Any ideas?

I get capped at 25 as well on single player but it looks exactly the same as on-realm, there's no visual difference or choppiness that I can notice. It's possible that the fps counter is broken on single player.