SNMP bandwidth tags toggle on map

I have just upgraded from Dude 1.2 to 2.2 on a Windows 2003 Server. Now I am having a problem with the snmp bandwidth tags on my network map toggling from no tx/rx numbers at all to the expected bandwidth readings. Then after about a minute they go back to tx/rx with no numbers at all. Any suggestions on how I can get this consistently bandwidth rates again.