I used another site
Whois record for 4.25.17.65 and the results say the IP is owned by
Las Vegas Little Theatre: By The Community, For The Community so I have no idea who owns that IP address try some of these sites and see if they all report a similar registrant
whois - Google Search....
The IP address is active and responding to ping requests and not all malware/spyware is included in the latest definition updates (spybot S+D allows you to download beta updates, try them) so you might/might not have an infection but any system constantly hitting that IP is curious and an anomaly...