Is this a firewall problem?

Have 4 servers connected to an HP switch which is behind a Netscreen

5XP firewall with an unlimited connection license. 3 of the servers are fine accessing Internet sites. 1 server is having problems. This server results in approx 7 out of 8 ping attempts to Internet addresses failing (DNS lookup succeeds). Doing a tracert shows successful hops up until the inside firewall interface...this is where it's failing (but approx 1 out of every 8 succeeds so it's not a policy on the firewall blocking anything). Also, from the problem server, pinging any server on the internal network results in 100% success. Any server internal or external can ping the problem server with 100% success. Can a bad nic in the server cause something as selective as this just accessing Internet addresses?? Or is this a possible firewall issue? Again, every other server and workstation has no problems..just this one.