Hello James and Welcome to Just Answer,
Sorry to hear of any trouble you may be having.
According to my notes, this particular system CAN be set to beep - when there are NEW messages recorded and waiting.
To do that, pick up any handset while the system is not in use (not on a call) and do the following:
1) Press MENU # ***** 3 9 (that takes you directly to the "Message Alert" control).
2) Use the UP or DOWN ARROW keys to highlight the setting you want (pick ON).
3) Press SAVE (to save the setting).
4) Press OFF button (to exit programming).
That should do it.
NOTE: This should make the MAIN BASE UNIT beep - and not the handsets.
Please give that a try and let me know your results.
If this works and has answered your question(s), please take a moment to rate MY service level (Excellent is my goal) so that I get credit for helping you with this question.
You should see some "smiley faces" or "stars" to do that, but please let me know if you do NOT see them or can not use them.
Thanks, ***** *****