This often happens when the recorded prompts are loud enough to override the caller's digits. It is almost as if the system realizes that the caller dialed a digit but didn't actually hear it. It doesn't start "listening" until the second digit is dialed.

There are two ways that I've been able to overcome this:

One is to re-record the main menu prompt in a male voice. I know that this sounds odd, but there was (and I believe still is) an issue known as "talk-off" that caused voice mail systems to act strangely when female voices were recorded. There was a claim that certain frequencies in a female's voice caused this. Call me crazy, but on a few of these cases, it seemed to work on a different brand of voice mail.

Secondly, I'd consider knocking the CO line transmit level down a notch in the KSU. This will bring the transmit and receive levels more in-line with the customer's current setup. The intermittent nature of your problem may be resolved by just going up or down one step on these level settings.

My guess is that the customer is on a channel bank or local pair gain equipment for their CO lines, where everything is very "hot".

Ed Vaughn, MBSWWYPBX