stokedboss
On my X2 tool bar, beside the CPU meters, there is a picture of a hard drive, and a memory module. When I'm running sonar (playback or record), the hard drive turns orange, but the memory icon stays greyed out. Why does this turn orange? Is there some reason?
It's only indicate that SONAR X2 read from disk and everything is normal.
http://www.cakewalk.com/Documentation/default.aspx?Doc=SONAR%20X2&Lang=EN&Req=ControlBar.09.html 
Disk Activity indicator 
. Measures how much of the available time SONAR is using to perform input/output functions on your hard disk. The size of your setup’s I/O buffer size (listed under File System in Edit > Preferences > Audio - Sync and Caching) determines how much time is allowed to perform disk operations and maintain uninterrupted playback. When SONAR performs disk operations, the
Disk Activity indicator changes color from
yellow to
red to indicate the time SONAR is taking to complete each cycle of disk input/output.
A red icon indicates
very high data activity.