Consider blocking the entire area code (xxx) or area code + exchange (xxx+xxx) if your blocker will let you. If you do not have a call blocker, there are available online and start around $45. http://800notes.com/nb/search?q=call+blockers
Called home phone last night (didn't leave a message, but they failed to hang up and I heard a woman speaking to a baby and a baby cooing in the background until my machine disconnected her) and called my cell phone the next day at roughly 1pm, left no message.