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If it's BBC (which it is) it'll be an old CDQ G.722/Musicam coder and a BBC Radio Projects mixer.

Apt.X is popular in radio outside the BBC, but for some reason the BBC never used it until recently. Almost all Radio 1 OB's now go over ISDN using SystemBase codecs. Apt.X sounds good, has low latency but is locked in hardware, which makes it expensive.
</nerd hat>