Inbound calls work fine but outbound calls fail everytime with dead air and then re-order tone. There is a problem with this router not receiving ground acknowledgment from the CO appears. "Show voice call sum" shows a status "fxogs_wait_tip_ground". I tried reversing the polarity which would cause this scenario per Cisco documentation and this did not resolve the issue. Last night I upgraded the 3745 to 12.3 version of IOS which allows me to run "ground autotip on the voice-port" this didn't resolve the issue. As a last resort to test outbound calling from the FXO ports we connected a Loop-Start analog line to the FXO port and we were able to make outbound calls. I checked the ground on the chasis with a meter and the chasis is grounded.
I have this problem too.