Customer has a BCM50 Rls1 with a T1 that has 6 channels. They are an answering service for several companies. On Friday morning I was informed that when customers dialed XXX-4811 they would get a fast busy. All other DID's worked fine. The local carrier troubleshooted the issue and found that the problem had to be coming from the BCM. We power cycled the BCM and that fixed the issue. This is the 2nd time that this issue has come up. The first time it happened it was every DID that gave a fast busy when called. The only error that I saw was Event 816:Unable to generate a tone on a particular DIA line TN. I have no idea what this means. Has anyone seen this before?