Post is sliding lower while riding. Not the dropper...the actual post. And it creaks. Any suggestions
Apologies for the thread revival. The seatpost wedges giant uses are pretty rough to deal with, especially on the anthem and XTC. For models with a rigid post and the SL seatpost, replacing with an alloy post would often help.
For droppers, or normal maintenance: Staying on top of torque spec and re-greasing with carbon paste frequently is the way to go. It's also possible that the frame was mis-sized - but don't go running to the LBS with that, I'd only seen two mis-sized carbon frames from Giant that would be covered under warranty in several years.