My windows clock is being readjusted periodically. At random times, I will see it 5 hours ahead. I have two boxes networked, both running XP, and both are doing the same thing with the clock. One will do it at a different time period than the other. I have ran AV on both of them (AVG and Trend Micro), as well as A-Squared, EWIDO, rootkit revealer, antispyware, etc. Both have a firewall up and properly configured. Nothing malicious has been found, but this is still continuing. Any ideas, guys?