Tim

At first should take a look to cable pinout (RAD documents) as pin 1,2, Transmit (output) and 4, 5 Receive (input) for Digium card you should use a straight cable (try to test with new cable one too). Second check Dahdi configuration parameters, use dahdi commands as; dahdi show status, service dahdi restart and check result, (could a mistake on parameter value on system.conf).

Mc GRATH Ricardo