I just put in my 2008 maps for the east coast and now when ever I zoom in, out, search for a POI or basically anything that requires the navigation to do something with the map, it makes some weird staticy noise over my speakers.
I took the DVD out and zoomed out a bit, and it still made the noise so it seems to happen whenever memory of any sort is accessed? Maybe there's some setting that got changed when I installed the 2008 maps and stuff. Hopefully there is an easy fix for this.