Arp Cache getting corrupted

We are using Digi single port (Digi SP 1) and multi port (TS 4 MEI) products. We have cisco 2950 and 3750 for backend routers and switches.
We have to constantly clear arp cache in the routers and switches to make the system of Digi ports and radio work together. Does anyone else has encountered this problem. Except for giving an IP address to Digi and turing Xon and Xoff off, the configuration is standard out of the box for all digi products. Thanks

We are having the same issues. Did you get any useful information?

You may want to try setting gratuitous arp on the units to see if it helps prevent corruption:

#> set tcpip garp=(30-3600 seconds)