Earbits seemed very focused on their value proposition to musicians. Their goal seemed to be "the Google AdWords of Music", but here's the thing: if you want to become the Google AdWords of music, you first have to become the Google of Music. The value proposition to the listeners is key.
To their credit, Earbits did have a value proposition for listeners: music discovery. But this meant their competition was Pandora, music blogs, Pitchfork.com, word of mouth, and all the other ways we find music in the 21st century. Another commenter here says "music is a tough nut to crack," but the real issue here is that music discovery is a tough nut to crack.
You could counter that Earbits differentiated itself by focusing on independent, unsigned artists; that's a noble mission, but if you're going to commit to that as your value proposition, you have to ask yourself if there's a market for it. Is finding unsigned artists really a pain point for most music listeners? I'm not convinced.
Anyway, sorry it didn't work out. Wish you guys the best of luck in your future endeavors.