I am trying to connect my laptop and the tv. I get great picture but no sound. Several sites have said to change the default in sounds to hdmi. When I go to the control panel, sounds, there is IDT but no HDMI. Now what/
I'm going to make four assumptions here; a) you have a TV with HDMI input, b) you have a laptop with HDMI output, c) you have an HDMI cable connecting the two and, d) the volume is up on the TV.
In control panel locate - system - device manager - sound, video and game controllers, you should have "High Definition Audio Device" available to select (possibly more than one) right click on on it and select "update driver software". You may also have to do the same with the monitor.
That may work for you, good luck.