Nothing records (flat line) in Audacity

PROBLEM: When I press record I get mostly nothing (a flat line) (sometimes there is a spike or some really low garbled voices for a few seconds) but no actual recording of audio. I am trying to record some old voice mails to my PC via my mobile phone with a male-male jack cord between the phone and the microphone jack on the front of my PC. When I play a voice message and press record nothing is recorded, just flat line.

I am running Audacity v2.1.2 on my Windows 10 64-bit OS.

In the Windows 10 OS I have configured:

Playback default: VIA HD Audio speakers
Recording default: Microphone VIA HD Audio

In both of those devices on my PC:
Device usage: use this device
Levels: 100%
Advanced: 24-bit 44100 HZ

In Audacity (upon opening the program or Transport rescan devices) - Edit - Preferences:

Host: MME
Playback: Speakers VIA HD Audio
Recording: Microphone (VIA HD Audio) with Channels = mono
Sound Activated Recording: not checked (off)

Under Recording I tried setting SW Playthrough on and off with no change (still flatline).

Why can’t I still record my voice mails from my phone? Is there a configuration problem on my PC, some audio setting on my phone?

Your settings look correct. Make sure the Audacity recording level is turned up (it “should” be the same as that you chose in Windows Sound). Set project rate to 44100 Hz.

You may want to check the cable you are using.

If you use your favourite search engine and look up your phone or phone operating system, there are usually ways to transfer voicemails to computer without recording them.