I have connected my TV audio to Harmon Kardon 347 through optical cable. There is no sound though. Any ideas?

Question

The optical cable is connected from the optical out on the TV to the optical 1 in or optical 2 in port of the HK 347 receiver. The HK doc says the opticals are mapped too Video 1 through Video 4 ports and should have analog cables also connected. I did so. And set the Video 1 to Optical. No luck. Then set Video 2 to optical. Still no luck. the L and R speaker letters are blinking on the HK display. Troubleshooting guide says your audio source is paused. Aargh! The Tv is not paused.

Answer 1

Optical audio connections can be finicky.

I had a similar problem with the optical output from my Yamaha receiver.  The CD recorder just wouldn't recognize the receiver's output.  In the end I had to connect around the receiver.

Check the menus on the TV to make sure that the optical output isn't muted or disabled.  Optical cables can be somewhat more fragile than RCA cables too so you might try picking up a new cable to see if that isn't the issue

Answer 2

I don't think you need the analog cables connected.  If you are using a cable box or satellite receiver, you should run the optical wire from their optical outputs directly to the A/V receiver.  Running them from the TV can sometimes cause problems.

Also, make sure that when you plug in the optical into the cable box's output, the free end of the wire should be lit up red.  If this doesn't happen, you may have a bad cable.