Thank you, I did everything you suggested, but the problem persists. I find it strange - I'm a layman - that even after disabling wireless, the default device "PULSE:Default|Bluetooth Audio (PULSEAUDIO)" is still the only option. If I enable analog sound, the option appears, but nothing connected to HDMI ever appears.
I'm going to buy a new adapter today, superior to the current one, which if I'm not mistaken is 2.5 amps, to find out if this could be the problem.