About the same time this was happening, I got Vonage service. This made me think that the problem was with Vonage since it sits between my router and cable modem. However, even after having re-arrange things by plugging the cable modem directly into the router (like I had it before I followed Vonage’s instructions), I was still experiencing this issue.
That got me to Googling about and I was lead to a variety of free DNS service as an alternative to what my ISP was providing. One was Open DNS which I tried for a day but it was too slow. Then I discovered Google DNS. The main servers are at 8.8.8.8 and 8.8.4.4 – very esay IPv4 addresses to remember! I changed it on my router’s setup web page to use these DNS servers instead of the ISP’s default. So far things are great. Web browsing seems to be a whole lot faster.
I’ll report back on this issue to see if the name resolution issue goes away entirely.