TRRS Y-cable splitter was my downfall

[drepouille]

I did some testing today, and discovered my problem with the Comtek and Lavalier receivers. It was the headset/microphone Y-cable splitter that I was using. I wanted to inject the sound into the microphone side of the splitter, while listening to system sounds (from Google Meet) using my earbuds on the headset side of the splitter. That failed miserably with the Comtek, the Lavalier, and everything else I tried. I guess that TRRS port just can't do input and output at the same time. No idea why.

If I just plug the sound source directly into the TRRS jack, and select the appropriate item (Mic in or Line in) from the pop-up, everything works fine. I just can't use my earbuds. I will need to use a USB headset to monitor the system sounds. 

Having said that, I have to say that the sound quality of the Comtek receiver is pretty bad, since the Comtek uses a fairly narrow frequency range. Any other solution would be much superior to the Comtek: the Record Out line level jack, the wireless Lavalier, or the wired Lavalier.

[russellhltn]

I'd imagine that most TRRS "splitters" will change the pin-out on the microphone side. Instead of a TRRS mic, it's expecting a TRS mic. The most common use is to adapt a dual-plug headset (twin TRS) into a single plug (TRRS). And the laptop will have to be set for "headset" to use the TRRS connection correctly.

[drepouille]

I think you are on the right track, and I should have realized how the audio combo jack on my laptop works long ago. I was foolishly connecting an audio source to the microphone jack of my headset splitter, and then telling the pop-up window that I had connected a microphone. Wrong answer! Since the headset splitter is acting as a headset, then I need to tell the pop-up window that I have connected a headset. (The exception may be when I try to connect a Line In signal, in which case, I should probably not use a headset splitter at all.)

I guess I am old enough that I assumed that an audio jack is a hardware device that always functions the same way. These TRRS audio combo jacks are actually programmable USB sound cards. The pop-up window is probably the way you tell the sound card driver how to program the electrical contacts within the jack.

[russellhltn]

I guess I am old enough that I assumed that an audio jack is a hardware device that always functions the same way.

Until you posted that pop-up, I thought the same.

[drepouille]

Since I realized that the headset splitter should always be treated as a headset, everything I have tried is working as expected. Wired mic goes in the mic jack of the splitter, and earbuds go into the headset jack of the splitter. No problem! I was even able to get the Comtek and wireless Lavalier to work with the headset splitter.