This is caused by some modems not sending the signal that RelayFax is looking for. There are two workarounds for this:
- Try adding &F1 to the modem init string.
- Add X4S7=30 to the modem init string. The X4 part makes sure all responses are reported by the modem and the S7 register contains a carrier detect timeout (in seconds). Setting this to an acceptable value will help RelayFax release the modem quicker when a carrier is not detected.