Qlink Q400's and tech problems?

[Jakef]

Hey there,
Recently flew to Sydney on a Qlink Q400 (VH-QOM) and as we broke through the clous and began the long approach to 16L there was a strange noise coming from the right engine or flaps (or gear).. Kind of like grinding or something..

Clearly it wasn't serious enough for the pilots to mention it to us but me and my friend sitting next to me both noticed it. After we landed it continued until we taxied to a gate between T2 and T3 and as soon as the engines shut off a bunch of engineers put a ladder up to the right wing between the engine and fuselage and got to work.
Now last year I was waiting to get a flight to CFS on a Q400 and we were delayed for about 20 minutes while someone came and fixed something in the same sort of place.

I suppose my question is is anyone skilled enough to know what I'm talking about, and is it a common problem? (Whatever the heck it is)
Thanks.