I am looking to get LG Sound Sync to work with my current speaker setup.
-- Status Quo --
My current Setup is as follows:
(PC --HDMI->) LG TV  --Toslink-> Cheap Toslink DAC  --3.5mm to cinch-> AMP  --copper cable-> Speakers 
The problem is that I can only control the volume in the following ways:
- On the PC in Windows itself - only if I am using it, not applicable for smart TV content nor Console
- As the AMP supports Bluetooth, I can cut out the DAC and control it that way, but that has a delay
- On the AMP, but I have to get up for that, which is what I want to optimize
When searching for LG Sound Sync I stubmled upon the hifiberry DSP repo  where the protocol was reverse engineered. Other than that I did not find any statements about the support of LG Sound Sync. ( has problems with it)
I still hope that I could replace my DAC with a DAC based on hifiberry. However, since I am not into Audio equipment that much I am a bit overwhelmed by the amount of different products and which to choose. (I already have a Pi 1 and 4 available.)
-- My Thoughts + Questions --
If I understand it correctly, I need DAC+DSP to modify the signal such that it is not as loud and then be analog. However, I feel like a DAC should also suffice, as it can read the toslink data and then change the analog output accordingly without having to modify the digital signal itself. (Why) Do I need a DSP?
Based on  the only two boards supporting digital input are "Digi+ I/O" and "DAC+ DSP", recommending the latter. Redaing its spec sheet, the input is "only" upt o 96 kHz while the output is at 192 kHz. Should I worry about some signal degredation there? My current cheap DAC supports 192 kHz, so in terms of quality this sounds like a downgrade. Also: should I worry about compatibility?
I also stubmled upon the Beocreate 4 channel AMP. This seems to support 192 kHz sampling. This would also replace my current AMP. What are the other upsides/downsides compared to the DAC+ DSP?
-- Overall Questions --
With which HiFi Berry devices does LG Sound Sync work? If it doesen't work out of the box, can I still use the HW to analyze the signal and mess with the software to understand the encoded volume?
What setup would you recommend?
Thanks in advance :)
-- Links --
 43UN71006LB https://www.lg.com/de/tv/lg-43un71006lb
 douk m1 pro, cf https://www.ebay.de/itm/266098426452