I also have a rattle in the seat belt adjuster area... very annoying and I believe there are some DIY solutions in the octave mk2 section on here but I didn't want to attempt it till my warranty is out (I have taken it back to skoda but they weren't issued a fix although they could hear it!)

The rattle from the seat belt adjuster seems to affect nearly all Rapids. Like you I plan to try the Octy fix once I am out of warranty.

Annoyed with it yesterday I smeared a small amount of red rubber grease along the top edge of the drivers window and closed it.

 

No more squeaks

 

I'm not expecting it to last but it's nice and quiet for now, doesn't look good also having a few smears of grease on the top of the window either, but at least I've found the exact place of the squeaking.

Edited 9 March, 201511 yr by MickA