I've been smelling "burnt plastics" for long long time. Main suspect was LED bulbs that weren't rated for "enclosed fixture", even though most fixtures are open. I think it's just the quality of plastics. Anyways, I replaced them with ones specifically rated for "enclosed fixture" (Home Depot's Ecosmart brand). Smell is gone a lot. But, there is still faint smell.
Ordinary bulbs fit in speakers? ...
If the bulbs are easy to remove, you could test the current without them. I think the issue is that the bulbs in the ceiling were replaced but
D. Hugh Redelmeier via Talk wrote on 2025-07-27 12:03: there's still a smell so the speakers are the next target to get rid of the smell. I don't think there are light bulbs in the speakers?
I would guess that gas emmissions from plastic decay exponentially.
In my experience, the emissions decay exponentially (or something, haven't measured). i.e. new $thing smells terrible for a few days / weeks then things go back to normal. /I'm enjoying the thought of speakers with light bulbs in them, please don't take that away from me...