Thanks for the heads up rob.
Here is what I did to resolved the problem:
I placed the SolarWinds server into IC (intensive care) being monitor by our other SolarWinds ( I had to create a WMI account for SolarWinds on the box), also added its gateway to be monitored and enabled IPv6 (the IPv6 was discussed throughout SolarWinds discussion boards as possible cause) - since then no more false alters...
Polling Engines Information:
On that single server we have over 18k elements, over 1700 Network Node Elements and over 17k Interface Elements -
Polling Rate: 153% of its maximum rate. Polling intervals increase if the polling rate exceeds 100% of the maximum rate.
Routing Polling Rate: 3% of its maximum rate
Hardware Health Polling Rate: 54% of its maximum rate
As you can see (by the above information) we are working this server hard - Our next step will be to look into SolarWinds Enterprise Operations Console (EOC) to split the load between our two SolarWinds boxes.
If you get false alters is not an easy fix but the issue can be resolved.