The biggest obstacle is probably price and a lack of deals with manufacturers/OEMs. It's well understood that consumer devices don't start selling until they hit certain price points. $299 is an example. That's darn near impossible RioCar to hit until you go into bulk manufacturing, which SonicBlue probably didn't want to risk.

OEM deals would have helped - imagine getting a combo CD/Riocar when you purchase a new Mercedes, but in general, it's a tough market to crack.

It also takes time for people to get it. I don't think Sonicblue did the most effective job marketing. It's well known that most consumer electronics firms send their products to reviewers and journalists to get the buzz going (most PR firms do this for them). I don't know how many Empegs were sent out; I don' t know how many Riocars were sent out when Sonicblue acquired it. There's been a lackluster acceptance of Empeg in the press; ever wonder why? People "get it" when they start using it. And most people need to be told to "get it". Can't do that without marketing or PR dollars.