Default CM11 nightly and random drops

I've install CM 11 nightly (last update from 12/19/2013) and I'm seeing my connection to the AT&T network drop randomly for a minute or so. If I turn off data then back on, it comes back up right away.

Is this a modem thing? I had the modem installed but saw the same problem. Is there something I can tweak or is this a bug? phone problem?