So, this morning I wake up: and my left ear is plugged again.
During lunch, I pressed the 'reset button' (tragus, that projection just forward of the ear canal) on my left ear. And - pop! - I could hear normally through that ear again.
Aside from the intermittent popping and slurping that goes along with this cold. Or whatever it is. And there's the familiar tinnitus. Rather louder these days.
Aside from that, though: Hey! I can hear in stereo! Wow.