I am working with a customer who has outbound calling issues. At certain times, seems like peak calling times, the customer is unable to call out, they receive a fast busy, they never lose inbound calling, even when they can't call out. We own the T1, as the ILEC, and have done testing, to no avail. We have monitored the T1 for 3 months, and have had no errors or drops. Since this is an intermittent problem, it is driving both the customer and me crazy. The PBX is programmed to the exact specs of our T1 provisioning group. We see no alarms in the logs when this issue happens. I just need a fresh set of eyes, or ideas, since I seem to be going down the same path. Any ideas will be greatly appreciated. Thanks in advance.