Application Lag

Hey All,

As of late, Premiere seems to be having a problem running for me. PLAYBACK is perfectly okay, however just overall moving through the project, everything has about a 2-3 second delay. This is obviously frustrating when sitting with a producer wanting to scrub through footage. (On another note any time I do anything with essential GFX, good luck. It's not even worth my time and effort as it takes so long).

--I am running proxies 1280x720 Low Res Proxy as H.264 seems to play out of sync. 

--I have cleared the cache, deleted render files, and updated the computer software, and Premiere.

--I have turned my playback resolution down to as much as I am able.

--According to my Activity Monitor, I'm only utilizing 50% of my RAM. But my CPU does seem to be a bit high. Could that be the culprit? If so what is the suggested "reasonable" fix?

I appreciate the help. Again, playback itself is okay. It's the clicking around the premiere, adding effects, and scrubbing footage that seems to not want to cooperate with me.