In cfmradio, just change cfmradio.c:430 to

to disable the builtin loop that copies audio to speakers. That way you can launch an external gstreamer loop that does whatever processing/delay you want, as suggested in the above post, method (a).

It would not be very hard to add a fixed delay to cfmradio itself (you just need to buffer up the raw audio data before forwarding to speakers), but you will indeed need some C and basic audio processing knowledge.