Do more Ethernet hangs up

[AustinT]

Hi
I am using a Do more that is talking to two devices . One is a serial device and the other is a pc using udp commands .Most of the time it works great but sometimes even days apart the udp commands to the pc hang up .  I am using an unmanaged switch and only sending from the plc .  If I power cycle the plc ,not the switch , it will resume operation for a few more weeks .  Where do I start to troubleshoot please ?
Thanks

[BobO]

You have a PM.