Hey,
I’m not sure if this is even possible to do cheaply but I just bought a pair of JBL LSR 305s and my goal was to connect them to my tv LG 55UK7550 via optical cable.
However, I noticed while looking for cheap DACs (such as Fiio D3) that they only do PCM decoding and not the required DTS and Dolby Digital.
Do you guys know any products that can do this? Apparently Fiio made one earlier called Fiio D07 but it is no longer available to my knowledge.
I don’t have a suggestion for you…but have you checked AliExpress to see if they have old stock of the D07?
You could also look for a used receiver that would get the job done, but it might be an overkill option
You can set the TV to output PCM only through the optical cable in the audio settings and it should work fine with the fiio D3 with all content.
Just note that the D3 has a pretty weak line-out, so you’ll get poor performance from it for those speakers without a preamp.
This sounds promising. You are sure that files (movies for example) played from an usb stick support PCM aswell? I am quite clueless how the whole audio format thingy works on TVs.
Could’t find any. 
If you want to PM me a test file, I can check for you. I have a similar setup, using an LG tv, output to my D70 DAC though optical. D70 only supports PCM. When I watch movies on VUDU, for example, they are encoded with Dolby Digital Plus or Atmos and TV downsamples them to PCM to output to the DAC.
You just have to be sure to set the audio output from “Auto” to “PCM” instead in the TVs menus
Yeah if you aren’t dead set on native Dolby or dts, this is a much better and easier option
Nah, I just want to be able to play the files on my TV via an USB stick. I think I’m gonna go with the Fiio D3.
Yeah, that will work just fine then, I thought you were looking for native decoding
Aight, thanks for the help guys!