Issue Possible Cause & Solution ReferenceSound cuts out; I can hearmyself through thespeaker.• You are too far away from the microphone.→ Try speaking closer to the microphone. —• The environment is not suited to speakerphone calls.→ Do not use the unit within 2 m of projectors, air conditioningdevices, fans, or other audible or electrical noise emittingdevices.→ If using the unit in a room with windows, close the curtainsor blinds to prevent echoes.→ Use the unit in a quiet environment.—• The unit was moved during a call.→ Do not move the unit while on a call. —• Objects are obstructing the microphone.→ Do not obstruct the unit during calls. Keep your hands, aswell as common objects such as folders, cups, and coffeepots away from the unit during calls.—• The other party is using a half-duplex speakerphone.→ If the other party is using a half-duplex speakerphone,sound may cut out occasionally during calls. For bestperformance, the other party should use a full-duplexspeakerphone.—• Just after a call begins, the unit may not have yet adjusteditself to the call’s environment.→ Just after a call begins, take turns with the other partytalking to each other. The unit will adjust itself inaccordance with the call environment so that both you andthe other party can hear each other as clearly as possible.—Phonebook ListIssue Possible Cause & Solution ReferenceI cannot add or edit entriesto the phonebook list.• The phonebook list is full.→ Delete any unnecessary entries. The maximum number ofentries in the phonebook list is 500 for the KX-UT123/KX-UT133/KX-UT136/KX-UT248 and 100 for theKX-UT113.Page 40Document Version 2013-03 Operating Instructions 85Appendix