I have kind of "ticking" noise from both sides of the car around head / rear side window area. I can hear them when driving around bumps, even with windows full down (hence not windows rubbing seals).
It is hard to investigate this when driving, since I cannot reach much behind me.
Anyone have any ideas from where this might be? Thanks

 

I probably have found the source - driver's B pillar. If car is stationary, door open, I grab the pillar firmly with hands and I "shake" the car, I can feel a miniscule wobble and hear the "ticking". The passenger's side is rock solid.
However, I don't know what to do with it. On UK forum I find one post that it is the collapsed glue between panels, no idea what to do with it...

 

Is it a ticking or a creaking? If its more creaking then its the rear taillights rubbing the rear 1/4 panels.

 

More of a ticking. Left side is the B pillar I am pretty sure. Right side is not the pillar, it goes more from a rear quarter of the car. Also this rear rattle seems to worsen after some time driving.

 

More investigation, I have lost half a day with this...
1) driver "ticking" I am positive it is from the B-pillar, since the left B pillar have a little play which right B pillar does not have, and also, the tickling is much worse when window is down. I suppose the windows push to the B pillar and fix it, if it is up.
2) passenger "ticking" not found. I have removed the whole trunk cover and its plastic sides from the car to eliminate this part, and the rattle is much more to be heard, so I am positive that the trunk lid actually dampen the sound. I wanted to check side-windows drain pipes, but I did not manage to disassemble the top partition cover.
3) I have identified a a new squeak, which is most likely what @WhiteTardis mentions. The whole left 1/4 panel of the car squeaks when even lightly touched, probably against the left taillight. Right side is solid everywhere.

 

Thank you, what is the fix? I cannot found anything on this...