Black Era 100 has white pattern inside from dust?

Try taking a soft brush, like a small paintbrush, and brush the dust out of the speaker grill. A vacuum with a brush attachment might work too.

I use canned air, carefully and NOT shaken to blow the dust out of several different Sonos speakers grills.

My first approach would be using a vacuum cleaner with no brush. I’d try to avoid touching the grill during this step because grinding the dust onto the grill surface might cause some etching. Next I’d add a brush to the vacuum cleaner. Using canned air would tend to push the dust into the unit, rather than removing the dust. For a small amount of dust the canned air would probably be OK, but I think that you would notice a large amount of dust simply pushed onto the speaker behind the grill.

After the major dust is removed, a damp wipe will help.

With the canned air the dust does get inside the grill but it is easy to keep blowing it around until it is all out.

For my Subs the speaker cloth dust cover has solved the dust issue a LOT cheaper than Speaker Skins.