I work for a small telephone company and we have a dsu 2. We have just put in a new voice mail system for our customers that has nothing to do with the dsu 2 but when customers call us about their vm we try to check it for them by calling from the dsu 2 phone system and any number with a 7 in it does not work. We can call any number with a 7 in it and it works fine from a 500 desk top phone. I have tried to change the DTMF tone length from 60 msec to 1040 msec and even tried IST trough dialing on and off.
Thanks for any suggestions
David