Remarkable Belgians performing, not live (6)

I believe the answer is:

signal

'remarkable' is the definition.
(signal can mean striking or noteworthy)

I cannot understand how the rest of the clue works.

(Other definitions for signal that I've seen before include "Communication with encoded message" , "Communication by sign" , "Remarkable; gesture" , "Gesture to convey information" , "Gesture with meaning" .)

I've seen this clue in The Guardian.

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