Heading to Fiji concerning foreign escape where there’s no waves (4-5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

F[iji] + RE (concerning) + ESCAPE. Another unfamiliar one: it’s “(of a radio etc) able to operate only … where the radio waves are not affected by surrounding objects..”, which doesn’t sound to me exactly like “where there’s no waves”, but perhaps others could clarify