We have a FXO gateway connected to a Quadro4x, we have upgraded the firmware to the latest and factory defaulted it after that as well. and the current settings on the epygi is any to any. Currently there are 6 PSTN lines connected but it seems that we are dropping some calls. Also there seems to be some echo on the line. I have changed the echo tail on the PBX and FXO to 255. Any ideas or help will be appreciated