io-net - High CPU Utilization

We are using QNX 6.3 on x86 machines. And use io-net with both tcp as
well as qnet options. Its a network of close to 8 nodes (3 QNX nodes
using qnet and the rest non-qnx using tcp). Over a period of 48 hours
of run time in this configuration, io-net starts becoming a hog and
starts of with 11% at power up and in 48 hours takes up close to
70-80% of the CPU on only one node which has tcp connections to 2
different non-qnx nodes and finally will lead to complete hang up of
this node. Any ideas or suggestions to get to the bottom of this