FXO disconnection problem. FXO directly connected to PSTN and doesn't hang up the call.

[admin_2]

Connection is

PSTN --- FXO 1750 --- VoIP --- 3660 E1 --- PBX.

The call is not disconnected when originated from PSTN, that is, FXO port in 1750 remains up. If I change to ground-start the call isn't answered by FXO port.

[#2]

If ground-start signaling does not fit the problem, you can also try some other alternatives, please follow the guideline http://www.cisco.com/warp/customer/788/signalling/fxo_disconnect.html