hooking up macbook to tv as second monitor

I bought a mini dvi to hdmi adapter to hook up my macbook to my Sony HDTV. I got it to work, but it blacks out for a couple of seconds at a time. I can't seem to figure out the problem. I'm wondering if this is common and fixable or if there is maybe a connection issue???

Makes sure the adapter and the HDMI connections on both ends are tight and secure. It sounds like you have a bad connection. If that isn't it, the adapter or the HDMI cable may be defective.

One of the connection ports may be bad. Try connecting another HDMI device to the TV using the same cord and vice versa with the MB.