Mine squeaks 
.
Nothing.
Have you checked your frame for cracks?
I use this stuff:
http://www.amazon.com/Ritchey-Liquid-Torque-Carbon-Components/dp/B001IOW71W
Tacx also makes a similar lube they call âassembly pasteâ.
you donât lube it, you use friction paste. i think mine is tacx.
On my Ti bike with carbon post I havenât used anything. On my full carbon bikes, I use carbon assembly paste. I think I have a tube of the Finish Line - Fiber Grip.
Nothing. Roadie with integrated mast. Crit and Cross bike with aluminum posts (why have a carbon seat post?). You sure it is the carbon post? If slipping, the Tacx paste is great. Likely the clamp/rails as the source of the creaking. REALLY like the new Fizik Cyrano seatpost (alum) with the very long lower rail clamp to keep forces even, can accept the oval carbon rails on new saddles, quiet, easy to adjust, plenty light, and not a bad price (compared with the gold std. Thompson).
Astroglide 
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climbing culk, thatâs from my buddy that ownâs a shop, i have used it and it works really well.
DanâŚ
Nothing. Oh hell! Nothing for sure!
The guys at the bike shop used a kind of reddish paste for mounting the 2 bikes I bought (cervelo P2 and S2) and on BOTH of them I was not able to fix the seat post by using the recommended torque: the seat always moves down after 20-30 minutes in a ride. Eventually, I get rid of all this f@#@# reddish paste by carefully cleaning up all this mess on the seat posts and inside the frame tube. Now, I can really fix the seat post in a given position using the recommended torque (written on the bike frame). I donât want to break the bike frame just because I would have to force a too high torque for fixing the seat post.
IMHO, putting any kind of grease on the seat post is a hell.
Also, before I remove this reddish paste, it happened that I heard some squeaking (as the poster mentioned). After I removed the paste and I carefully respect the maximal recommended torque â no more squeaking.
_michel