I am trying to allow an external caller to access the voicemail menu. So, when the voicemail picks up, they dial 99 and then enter a pin number, then press 9 and access is granted to the menu options. My setup is as follows: POTS to MP114 to 3CX V9. However it only works as fiollows: 1) If the call is internal (ie internal phone connected to my MP114), 99 can be dialed from the dialtone and menu access is possible. 2) If the caller is external then I wait for voice mail to activate, but when I dial 99 I briefly get the on hold music then it goes back to voice mail again. Any ideas?