Is there something going on with the us-east connection?

Twice in the last 24 hours I've noticed my hash-rate went to about 30% of normal throughput and cgminer switched me to an alternate pool address.

My miners haven't hiccuped and show normal hash-rates - but the effective hashrate on the dashboard dropped dramatically.

First occurrence was at 23:15 CST on Jan 3
Second was at 10:40 CST on Jan 4.