I got a replacement rubber from ebay for my bee-sting aerial for just under a fiver, here is a link.
Audi A3, A4, A6, TT Roof Aerial Rubber Gasket Seal | eBay
As for the RNS-E you could try Jack Walker Partnership at West Craigs Ind Est on the Turnhouse Road which is not to far from your work.
I was a tad confused by your last comment, but then I realised it was you!
The Audi's amazing powers of self healing seem to have done the trick though, as the satnav is now picking up 9 satellites.
Long may that last!
I was reading the news about this huge solar flare that's been bombarding us over the last couple of days and it dawned on me that the GPS satellites themselves were probably banjaxed.
Are you going to do the aerial grommet?
If so you can get to the bolt via the rear roof light to undo it.
Give me a shout if you need help.
I went to Jack Walker today - I've been losing sat nav intermittently so took it into them on your advice.
They ran a VAGCOM diagnostic and found no error codes from the aerial, GPS, or otherwise. The system was all clear.
On the way home from work, satellite signal varied from 0 to 5. Normally I have between 7 and 9. As of now it's reading 0 again!
I also had them check out the AM reception, which has totally deserted me, and they couldn't find anything obvious (FM is a bit dicey too, but not as bad). They're recommending a new antenna. I've tried a halfords replacement aerial, but apparently the GPS system needs a specific bee-sting aerial so it might be a problem with that, although it's nothing obvious.
I mentioned the water in tailgate previously, and I explained that I thought the antenna booster was within the tailgate somewhere. Do you know if this is the case? It's possible that there's a bad earth in there.
For me, the fact that the GPS signal is coming and going would suggest a bad contact, bad earth or something along those lines, rather than some major issue with the system itself.
One minor gripe I had was that they managed to scratch the corner of the RNS head unit when they were removing it - not good. A blemish on an otherwise unblemished car!