I have the same issue,
it appeared in ML in the status bar, however with mavericks it has disappeared.
MBP Late 2012 13"
Detailed in another post
I have solved the problem. Hopefully this helps others.
I was looking for a Mac cleaner online, and settled on http://macpaw.com/cleanmymac - Very slick interface, great program feel. Very satisfied.
As I went through the different items in the "Clean" menu, Extension Mgr > Login Items.
I had a slew of stuff starting up, that I could not see under System Prefs > User Accounts > Login Items.
I recommend going through it and removing all that you can from there.
I took out Google Chrome Updater -- I like updating on my own
Parallels - no longer used
Steam -- this program bogged my system when I had it
and a few others that were not around.
I did a reboot, (which booted faster btw), and Voila my AirPlay icon has returned.
No stuttering, Audio matches Video.
Very Happy to Have AirPlay back again!
(I didn't realise how much I used it)