Geomamma listening is a big issue for our 4 year old son as well. DS's preschool teacher recently asked if he had a hearing problem because sometimes they have to ask a question several times before he actually engages - I thought is that all! His hearing has been checked out several times because of early middle ear infections including once by a specialist who on hearing him talk said he'd be very surprised if there were hearing problems - advanced speech for age usually indicates no hearing issues.
As an aside either Gross or Ruf state that a significant number, I think it was 80%, of gifted kids they researched reported as having repeated middle ear infections. They weren't saying it was causal - just of note.
I think jojo hit the nail on the head with is being an attention issue - so much going on in his head competing for attention. One solution we've found is a touch on the shoulder when we want to talk to him gets his attention. I also use a countdown from or up to 10 which for some reason acts as a circut breaker for whatever he's thinking about. Distraction after he's asked the question may also be an issue - my DS can certainly be distracted very quickly.
