sabbertooth z77 Mother board Won't run at 4.6gig anymore

[radioguy728]

please help my system keeps freezing up,sometimes the sound card is not recognised.Everything was fine for 2 years
then this started to happen.Now i cant go over 4.4ghz and my memory wont run at 2133.
It seems to run at 2000 when i set timings to 10 9 10 24 corsair vengence red 2133 spec:11 11 11 30 2t
Not sure if its the board or the memory controller on the I7 3770k
doesn't seem to matter what i am running gaming or browsing,installing a game.
I sent the board to Asus they claimed they fixed it.They want me to do a cross shipment.
sorry if this post is in the wrong area,any input would be great.
thank you in advance