Outbound calls/no ringing

I opened a ticket on this, but was curious if anyone else has seen this.

I had 2 numbers (one on Saturday and one on Sunday) that when I called, I just got dead air. I tried 2-3 times in a row, and then called my cell to see if my phone was working. My cell phone rang fine (and I heard the ringing on my Voipo line). My call log shows the dead air calls as 0.0 length.

I ended up making the outbound calls on my cell phone both times, and the call went through fine.

Anyone else seen this? Any ideas?

Dan