Download/install/run pingplotter.
Leave it running/pinging the IPU card.
Voip is a realtime protocol (RTP). Most likely either your or the IPU end had severe delay or packet loss. Computers don't care cuz if a packet is lost, the other end asks for a resend.
Not so with voip, no packets are ever resent.
Leave pingplotter running ALL THE TIME at about 2.5 sec intervals. When you experience the problem again (and you likely will) you will see which router hop is being bad.
Were you or someone else at home downloading large files at the time? Maybe a bunch of Windows updates at the IPU end?
Dave
