Telephone FAQ

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How to enable debug information

Quit Telephone, open Terminal and run:
defaults write com.tlphn.Telephone LogLevel -integer 4

Launch Telephone, reproduce the problem, quit Telephone, and examine the log file.

To set the default log level:
defaults delete com.tlphn.Telephone LogLevel

Where is the log file?

/Users/username/Library/Containers/com.tlphn.Telephone/Data/Library/Application Support/com.tlphn.Telephone/Telephone.log

The log file is overwritten every time Telephone starts.

I have sound problems with FritzBox

Try to enable “Use only G.711 codec” in Telephone sound preferences.

I hear echo

An echo occurs when the sound from the speakers is captured by the microphone. The cause of the echo is usually on another end of the conversation. If you hear echo, please ask another party to use a headset or headphones.

Another party hears echo

As in the previous question, using a headset or headphones should help. In this case, however, the cause of the echo is on your side.

Which headset can be recommended?

Even simple headsets that come with mobile phones can significantly increase the sound quality and reduce echo. A bluetooth headset can be a convenient but not the most reliable choice. The bluetooth paring problems in the OS are still not uncommon. The most reliable choice would be a higher quality USB headset. Plantronics .Audio 400 DSP is an example of a decent portable USB headset.

How to send tone signals

Just press digits on the keyboard when the call window is active. Asterisk (*) and number sign (#) are also allowed.

Why sending tone signals doesn’t work?

When calling regular phones, sending tone signals must be supported by the VoIP gateway. If the gateway does not support RFC 2833 or SIP INFO DTMF standards, the signals will not be sent.

How to place a call on hold

Press H in the active call window.

How to mute the microphone during a call

Press M in the active call window.

How to create sip: and tel: links

Here are the examples:
Call John Smith: <a href="">Call John Smith</a>
+1-234-567-8901: <a href="tel:+1-234-567-8901">+1-234-567-8901</a>

Please note that there are no slashes after the URI scheme.

How to make calls from a text selection in another application

You need to enable Telephone: Call in macOS Services. Go to System Preferences > Keyboard > Shortcuts > Services > Text. Check Telephone: Call and optionally add a keyboard shortcut. Now if you select a text in another application, then right-click on it and go to the Services section, there should be Telephone: Call there. If you click it, Telephone should use the selected text as a call destination. It is possible to use a keyboard shortcut instead of clicking and navigating to the Services menu.

How to close missed call windows automatically

defaults write com.tlphn.Telephone AutoCloseMissedCallWindow -bool YES

Where can I store SIP addresses?

You can save SIP addresses ( in macOS Contacts app as an email with a custom label sip. Telephone autocompletes such addresses and Contacts app plug-in shows Dial with Telephone for them.

Which codecs are supported?

  • G.711 family codec (PCMA, PCMU)
  • Speex/8000 (narrowband), Speex/16000 (wideband), and Speex/32000 (ultra-wideband)
  • Opus
  • iLBC
  • GSM
  • L16 family of codecs

I’m getting ‘423 Interval Too Brief’

You should increase the re-registration time interval in the advanced account settings according to your registry server configuration. If you’re not sure what the proper value is, try 600, 1200, or 1800 seconds.