Interesting, I have a Pixel as well (8a) and it has a quirk associated with the USB C output. When I use wired (as opposed to bluetooth) headphones to listen to my Audible app, the first second or so of each paragraph of narration drops out. After hours combing Reddit I found someone who had the same problem and they kludged it by playing a whitenoise app in the background. I did the same and it works most of the time, but there’s no problem at all when I use bluetooth (quite the reverse of the usual situation, I know).
Anyway, to go from my phone to my 5.1 home theater system I use a bluetooth dongle on one of the 3.5 splitter ports. On the laptop side I bought a special little box that extracts the audio from the HDMI out signal of the laptop and sends it as stereo via 3.5mm to the other splitter port. My 5.1 home theater system doesn’t have any way to input a 5.1 signal other than from DVDs but the special little box can extract 5.1 and output it via an optical cable as an option.