Troubles generating things to talk about.

Anyone have difficulty coming up with things to talk about (especially verbally), as if your mind is always blank? I really struggle to contribute to conversations and steer them in any meaningful direction. Of course the obvious explanation would be a lack of interest and experiences, but it seems deeper than that. I watch people converse with others so naturally and fluently, while I prefer to remain silent and observe (actually I prefer solitude and to be far away from people).