The dome is designed not to come off accidentally.
It should not be remove by simply pulling it off the receiver (speaker).
Pinch the dome between thumb and forefinger so that it is ‘bunched up’.
Peel the dome off the receiver in a similar motion to peeling a banana.
It should be noted that each dome should not be removed and replaced more than 2 or 3 times before it is discarded for a new one.
Find the hole in the rear of the dome.
Locate the receiver into the hole and push the dome straight down onto the receiver.
You should feel the dome locate on the fixing barbs.
Finally push down on the dome to ensure it is firmly in place