I can confirm this - AV has been buggy for some time now and I have tested that the problems arise only in that instance because i did AV with a mix of HM and EM primals and other dungeons. Every time I went to AV I had problems, whereas in other instances I did not have any problems.

Problems with AV:
*skills don't register (even though CD's go off)
*interaction with objects (fruits) are slow on first boss - you need to press several times and it takes at least 5-10 seconds for the press to register.

Usually i experience this starting boss 1 up to boss 2. After boss 2 and during boss 3 the encounters seem smoother.