I have 2 Samsung NU7300 55" TVs and 2 pairs of Edifier R1280DB speakers and 2 Asus PCs.  The TV and speakers both have optical audio connector sockets.  The optical output worked on the first one and then stopped months ago.  The new TV setup (in the gym room) did not work at first and I changed all values to PCM in both TVs.  Then I changed the HDMI connector to the second socket in the new one and the optical connection worked.  Tried the same thing on the older one with no luck.  The Edifier speakers work with bluetooth on the computer but bluetooth is not included on the NU7300 TVs.  The TV sound functions on both units and show up on the 2 PCs as the default player device.  Both TVs are connected to the PCs as an extension viewing screen. I tried putting a bluetooth dongle into the USB socket on the TV but had no luck with that either.  I have reset TV factory setting with no luck.  Any ideas please?  Thank you

Apparently you need to change the "expert settings" to PCM whilst connected to the source/app that does not work properly.

 

https://us.community.samsung.com/t5/4k-8k-and-Other-TVs/Optical-audio-output-not-working/td-p/214630/page/3

 

This may explain why it worked when you switched HDMI sockets.

 

If you are only using the TVs with a PC as the source then it may be simpler just to bypass the TV audio altogether and use the BT sound output from the PC direct to the BT receiver on the speakers.

Thanks, will give it a try.  This is a problem suffered by many and it is a surprise that Samsung has not made an effort to provide a fix with their smart TV updates.  The TV sound is OK, just not as good as the Edifier speakers.  The Edifier R1280DB are not costly and consistently get rave reviews, by the way.  Any thoughts on plugging a BT dongle into a USB socket on the TV?  Thanks again.

4 hours ago, notrub said:

Any thoughts on plugging a BT dongle into a USB socket on the TV? 

That wont work.

 

Best to pair the BT on your PC directly to the BT on the speakers, bypassing the TV altogether. That will only work when the PC is the source, of course.