elements 7: pops and clicks when playback starts

Hello, I have encountered a problem. When I start playback in a project from anywhere in the song I get a loud pop. I also noticed when I navigate to a part in the song the disk cache spikes and then goes away. I am running a 64bit, win8, i7, 8 gigs of ram, cubase elements 7, 16 tracks of audio with a stock compressor and eq on each and some external free ‘exciter’ plugins both 32 and 64 bit on a few of the buss tracks. I have not ‘optimized’ windows yet, but I feel that the pc specs would handle a ‘garage band production’. I think maybe the problem is the non-stock plugins but they have been around and ‘tested’. The reason I searched these out was because the ‘saturation’ module on the channel strip in cubase was causing problems…so I found these and liked them. They are FerricTDS, TesslaPRO mkII, and the Flux: BitterSweet v3. Any thoughts or suggestions? Thanks in advance.

More RAM?