Hi
The RRC.s doesn't know anything about what software are connected, it just transfer the data. For the RRC-micro it's different as it has to communicate with the Control software inside the the PC.
The serial link in the RRC can never hang up, it just sends the data. If something hangs up it's probably the PC-software. As far as I remember the Tentec uses the same type of protocol as Kenwood, Elecraft etc. where every message are ended with a ; . The RRC buffers data until it receives the ; then it sends the buffered message to the other end, which starts to send it to the radio over the cable. It's not much we can do about it. Probably it's the PC-software which expects answers from the radio within a very short time, and if the answer is to late or missing it will hang up. As programs often are made to be used only with a 2 m cable direct to the radio, the developer have not thought about missing or delayed answers and do not handle the situations correct.
I guess you have tried in mode 1 or 3 also, and have you tried with TRX manager.
Im sorry but I don't think there is much that we can do about it at least without the radio and the PC-software. And even if we should have the equipment I think that in the end it will show that the problem is not in the RRC.
73 de mike