I've had this problem before and can't remember how I resolved it. The Meters rise to a peak level and freeze (hold that position). They are normally dynamic and move as the SPL moves...I need to see the dynamic range as it happens.
A very interesting tip and it worked...although I don't know why the anomaly started, as I keep my computer on most of the time (some say Yay, some say Nay) for that....