Hello, I'm having problem with a phone where the user must hit the speaker button or outgoing button to get a tone on the handset. The lever on the phone where is tells it if is use is also not working. I've looked in the settings with no success. I've tried changing the phone out with a new one, but same problem. Thanks for the help. Any questions, or need me to clarify, please ask. It's also just the basic digital terminal. Model 520 4300.