Why does clicking on the recording tab under sound preferences change my audio?

I have a Philips SHB8850NC bluetooth headset. When I'm playing audio through this device, if I click on the 'recording' tab, the audio mutes. As soon as I change the tab back again, the audio resumes.

There is a slight static click when I switch the tab. I'm not sure what this means, but thought it was worth noting as it is audibly different from performing a software mute button on e.g. my keyboard (which mutes/unmutes without static click).

I also noticed that occasionally while communicating over via headset plugged into the 3.5mm audio jack of my laptop, people would complained about my voice being extremely soft. When I clicked on the recording tab, it would fix the volume until I changed tabs.

What is going on here? Is this intentional design (and if so what is the rationale)? Is there a way to prevent it? I am frequently fiddling with my microphone settings because of the above and it would be nice to be able to do so without muting my audio.

• Windows 10 x64 Anniversary Edition 10.0.14393 Build 14393
• Lenovo W540
• Philips SH8850NC headset

Edit to add images.

Basically if I have this window open:

if I click on the recording tab it will take me to the window below, and my audio is muted.

As soon as I click on another tab (playback, sounds, communications) the audio resumes.

I believe this is intentional behaviour of the implementation of these headphones. The idea is that music audio is pushed through the 'speakers', and voice audio is pushed through the 'headset'. As soon as the 'headset' or 'mic' becomes active the device assumes that there is a voice call and makes a (questionably reasonable decision to) mute the music channel.

I guess this workflow is most appropriate for car/handheld devices but I use this headset on my PC where I'd prefer to have better quality voice audio (my VOIP client will allow me to pump audio through the speakers, and it is noticeably better sounding than headset). But such is life.

Curious if this is the norm for bluetooth headphones with multi source? This is my first pair.