I am using Beyond ATC, and have a Bose A20 set from flight training. It works great with simming and talking to Beyond ATC, except I can’t hear my mic (like you would in a real aircraft). I am connecting it via bluetooth to my pc. I have gone into sound settings and tried selecting “listen to this device”. I can then hear my myself on mic, but audio from the sim is gone. Is there a way to have both? Thanks!
If you’re using Bluetooth don’t you get lag when hearing yourself? Like an echo? I use a wired system and it’s simple if you can find a way to hear sim and phones via Bluetooth with low lag I’d be interested too. Are you sure the phones are not just looping the mic sound direct to your ears bypassing the pc bt connection entirely? That would explain zero lag and also zero sim sound.
On your windows sound settings for the microphone, isn’t there a ‘listen to this device’ setting? If there is, then maybe try switching it on and select your chosen output device, probably your headset, to play it on. That might bring the desired effect, but it’s worth a try either way. 
No lag at all, but you’re probably right. Being that the sim sounds cut off, it is probably just directly giving me mic sound. Idk
Yes, there is. I have switched it on, and I can hear myself great, no lag. However with that switched on, there is no audio from the sim. Even tried with just youtube, etc. All sound is turned off when I’m listening to the mic. If I switch it off, normal audio comes back. I’ve tried tinkering with all different inputs. Reading some places that Bluetooth may not be able to handle both at the same time? Isn’t this 2024? lol
What /how are you using to switch to mic? Switch WHAT on exactly? Yeh it’s 2024 but Bluetooth itself cannot handle data very fast. It’s certainly possible to hear everything that’s just down to mixing the input sources. It WILL sound delayed though.
Wireless audio is a different ball game. And yes bluetooth IS wireless duh lol but… It’s a consumer tech not pro.
Switching in the sound settings on the PC. When @HawkMoth9135 said “listen to this device” setting. When that is on I can hear my voice no lag, but all other audio is cut off. Once switched off, audio comes back, but my voice on mic is gone. Can’t seem to get both at same time.
Try right click on the speaker icon bottom right status bar. Select open mixer settings. Every sound source can be assigned to each output source. Depending on your Windows version you might get different screen to do this Your output choices are system (sets default) and each input. Selecting default in output input sound goes to whatever you set in default.
Start off by setting all inputs to system default THEN change system default to your headset (presuming that’s where you want the output to go to)
I THINK your headset is intelligently rerouting your mic direct to headphones avoiding lag by bypassing windows entirely which would also cause no system /game sounds to be heard. Bit of a guess tho!
I think that the headset is interpreting your mic use here like a phone call and muting other sounds, maybe silencing some of them. The A20 is an aviation headset and presumably has twin aviation plugs at the end. If so and I tried this yonks ago with FSX, around 15 years I think - I purchased an adaptor which allowed sidetone back through the headset. I cant remember who made it, but you should be able to google it or so ething like it. As I remember, there was a slight lag in sidetone. Nothing bad, but the killer for me was a non Bose headset which left your head feeling squeezed like a toothpaste tube after an hour or so. I wish you luck.
It may have been something like Flightsound, but an “Aviation headset to PC adaptor” should get you started. If that thrrows up no joy, try PC headset with sidetone or something.
Edit… Yup! It is flight sound. Still in business but as per my last, you may well find that a PC headset with Sidetone search will give you a cheaper and quicker solution.
Go to control panel > sound > select the communications tab and do nothing
apply > ok