Webcam microphone not working in Skype

I recently installed Skype and have been testing the Logitech C270 webcam which I have. The video works fine. The microphone doesn’t; as follows. (a) I am unable to make the listener hear my voice when using Skype. (b) I have gone to Zorin’s Settings-Sound- and then Input. Choose a device for sound input–microphone Webcam C270. All ok. Microphone volume buttons etc all turned on and detects sound. © Am able to record an audio message and send it to the recipient via chat. (d) The Skype Echo test service cannot, however, hear my voice or record my test message.
I see an article on PulseAudio, but am not sure whether this applies to microphone problems as well.
Hope to find a solution since I’m on the verge of converting someone from using Windows 10!

Could you try sudo alsamixer in the terminal and see if playing with the mic setting helps?
You can also try the solution here:

Good morning. Thanks for the reply; I’ll try those out this morning and come back here again with any results.

Well I’m jiggered, the microphone is working fine this morning, without any further interference from me. Maybe something reset itself when I turned the PC off for the night.
However…I’ve made a note of the suggestions for future reference, in case there’s a problem again. Always good to have a plan!