As the title (topic) says.
A person called me from 1500k away. He couldn’t hear me. Someone in the room just called
(to test it). I could hear them (on the L5 phone) but they couldn’t hear me.
Yes, “mic” ( I gather that’s the Wifi switch) is On. Tested by switching Off then On and still can’t hear me.
Yes, “mobile” is on. Tested same as “mic”.
Of note:
Mute icon is grayed out with a “X”. Speaker is also grayed out.
When called dos call, I hear them on speaker (?) / ear slot.(?)
~s
Modem partially went to sleep when this happened to me. I set timeout to 72-hours and if fixed any cna you hear me now?" issues
The “mic” switch … is the mic switch. That’s the one that is lowest down (assuming that you have the phone the normal way up) or, that is, the one closest to the centre of the phone (for normal or upside down or sideways 
).
If that turns out to be the problem, you are not the first person to report “caller can’t hear me AND oops, I’ve killed the mic so no actual surprise that caller can’t hear me”.
Try installing GNOME Sound Recorder, then recording audio from the microphone using the app to determine if it is fully functioning or not:
sudo apt install gnome-sound-recorder
Considering I haven’t given my phone number out, 99% of the incoming calls are spam. It suits me just fine. My only use is to call my android in my house when I’ve misplaced it. The other use is a space heater. (No problems with sub-zero temps with an L5!)
How so? I would have thought that, for most spam calls, you want it the other way round: i can’t hear caller but caller can hear me. So you can abuse the crap out of the illegal and unwanted spammer 
while the spammer gets to advertise nothing and likewise can’t scam you if the caller is a scammer.
Any progress on this, @Sharon?
Yes. Below.
Duh. 
In my own defense, I use a $40.00 pocket camera that I take with me along with L5.
Ergo, I shut the L5 camera Kill Switch to off - and left it off, not realizing it also kills the mic.
I should have checked the Docs but I plead innocent cause I thought I’d end up asking such a question anyway.
~s
Problem solved but I will get the recorder anyway. Thanks
~s
My problem turned out to be me.
Your reply may be a possible solution to my other problem. I am going to try your suggested setting as it may help prevent having to reboot each morning in order to get WiFi started again.
~s