Headset/speaker crackles, with browser windows opening automatically

[SenaCat]

Hey folks! First time on the forums, but generally I can fix my own issues so I haven't needed to come here. Until today.
Mint 19.3, Cinnamon 4.4.8

A brief chain of events to try and run this down, since I can suspect a partial culprit but it doesn't all add up.

> Occasional anomalous crackling/fuzziness in my headset & speaker audio, but most often when they're first switched to (As in, when a headset is first plugged in, or audio switches to the speakers when the headset is unplugged. The crackling disappears at some point either way and audio is fine after that. The crackling doesn't appear on start up.
> Had irritating static in my mic input, so went and got the echo reduction module for pulse, that problem is resolved.
> Either before or after the echo reduction module, every time I plug in or remove an audio device on my computer, my default browser opens exactly five separate browser windows on the active monitor, all on the home page. Harmless but aggravating.

I'd have just run down the crackle, but since I can't *quite* remember the timeline on the browser windows popping up compared to the echo module, I figured I'd combine the issues here since the crackle and browser windows might be somehow related. Browser is Firefox.

Audio:
Device-1: AMD Ellesmere [Radeon RX 580] vendor: Dell driver: snd_hda_intel
v: kernel bus ID: 09:00.1 chip ID: 1002:aaf0
Device-2: AMD Family 17h HD Audio vendor: Dell driver: snd_hda_intel
v: kernel bus ID: 0b:00.3 chip ID: 1022:1457
Sound Server: ALSA v: k5.4.0-77-generic

[SenaCat]

Update: Now running Linux Mint 20.2 Cinnamon 5.0.5
The browser popup oddity has stopped, the audio crackle remains, it lasts roughly five seconds, and then ceases. As well, the echo cancel has been removed as well by the update to 20.2 so that wasn't the issue either.