My girlfriend moved here from Chicago after reuniting, sadly, after a friend's funeral. When we started talking long distance, it was just as friends and it was primarily through texting. As we did this for about 8 months, we began to become more and more interested in each other and started texting and talking on the phone more often, but a real phone call didn't happen all that much in comparison to texting. I liked it better that way, because as someone mentioned, I really don't like chit chat all that much.
What I can tell you is when we were just talking to each other merely as friends in the beginning, I wasn't obsessed with talking to her because I didn't think she was into me all that much in that way. Days would go by and she'd eventually text or I would, and it didn't matter. We would talk about other people we were seeing or fucking at the time and we wouldn't flinch about what the subject matter was because we didn't know we were interested in each other.
Eventually as we became more aware that we liked each other and we started texting more frequently, if she mentioned hooking up with someone or mentioned some dude or whatever bullshit I didn't particularly want to hear about, I may have gone a few days without texting, to which she would eventually send me a "Hellllloooooo? Are you there?" text. It was cool and it let me know that she cared, but here I was trying to distance myself a little bit because if we were interested in each other, why would we be discussing who we're fucking anymore?
So I don't know if that helps you but, have you said anything that has possibly given dude a bad vibe? Perhaps he has decided he really isn't in to you, but that isn't what he's saying. So maybe you said something he didn't like? We really can't guess; he may want you to be more interested and is playing hard to get in some weird fucked up way kinda like I did, or maybe he's seeing someone else or someone has his interest peaked for whatever reason.
Just be up front and honest and you probably won't go wrong. If you have feelings for him, fucking call him and go out and see to it that you are showing some real interest to take it somewhere else besides just sex.