Panasonic KX-TGM420 Operating Instructions Manual page 59

For base unit (using a handset):
[MENU] [#] [*] [7] [5] [0]
2 [ ]: Select the desired setting.  [SAVE] 
[OFF]
Note:
• If you dial a phone number quickly, the handset
may not announce the dialed phone number
correctly. For best results, dial slowly, and wait for
the handset to announce each number before dialing
the next.
• Some names may not be announced properly.
• Talking phonebook is not available in the following
situations.
– When the base unit is in use (on an outside call or
using the answering system)
– When another user is searching the phonebook,
caller list, redial list, memory dial, or call block
list
59 | P a g e