Many people complain that they sometimes miss calls on their iPhone because it only rings three times before diverting the call to your voicemail system. The length of time that your iPhone will ring before activating voicemail is actually controlled by your mobile network.
With Call Recorder, you simply make a call from the app, and it’s automatically recorded and stored locally on your phone. From there, you can play recordings, email them, or save them elsewhere on your handset as a .wav file. Calls are made over the app’s VOIP server, rather than over your cellular network. (So just make sure you’re on a good Wi-Fi network to ensure the best call quality.)

A word of warning: These greetings will not do you any favors if you're in the midst of a job hunt or work in a conservative industry. Always remember your target personas. If there's a chance they won't appreciate your sense of humor, opt for a straightforward greeting instead.
On inbound calls the phone will only ring once the jump to the next step in the call flow whether it is voicemail or another extension. This issue only happens on Monday, by Tuesday it has resolved itself somehow. This is defiantly a pattern as this is the 3rd Monday this has happened on. All 3 customers are running on Linux Debian 9.