Here's one to puzzle over.
406 control unit 2.1.35
2 x 16 port analog trunk modules
2 x 30 port DS modules
4400 series phones
no IP phones or VCMs in use
this system has been up since last summer, and those 3 lines were not a problem until now.
trunks are analog, although the souce is a SLC rather than copper pairs back to the CO.
3 particular trunks fail to make outbound calls (caller hears nothing during tha call attempt), but inbound comes in on them fine.
all 3 trunks sound good and clear with test set, and you can go offhook with the test set and call out fine.
Telco provider checked all trunks, says they are good, on and off hook voltage is within their parameters. (I was offsite, and didn't realize that loop current was not tested until the tech had left).
If you swap one of the problem trunks with another trunk that works fine, the problem trunk is still no joy on outbound attempts. The other trunk in the swap works fine in the problem trunk's original port. Also tried the problem trunk in the other module on the same system - no joy.
Is the IPO perhaps less forgiving of voltage or current being at the edge of the carrier's acceptable limit?
djtelco
