PUSH information to your readers to inform them of your latest release; appearances, contests, free reads, etc., via Facebook, LinkedIn, and GoodReads, or whatever social media tool you like. There's no way to know where the new buzz will be. Maybe it's your knitting network that's all abuzz over your book. Those knitters probably love audio books, and then buzz about your books into networks that could be global.
You are missing the bulk of your audience if you only connect with writers.