Samsung_HD_Tech not interested in responding to this?
This question is regarding the Samsung TV combined with a Samsung soundbar that I have at my house in Chiang Mai, Thailand. Hence the model numbers may not relate to US versions but I would reckon that the principle will be the same [?]. TV = UA46D5500RRXXT and soundbar is HW-J450. I have tried all the recommended connection options [currently optical ] but the max vol sound level is simply not what I expected. TV switched to external speakers; I did find a small improvement when I set the basic TV vol up to max before switching to external speaker mode. If I use the 'Smart' aspect and load a YouTube music video the max vol is much greater. Most of my viewing is via an android box connected via a 30gig FO link.
Footnote: I have had a good historical link with Samsung products but [related to this question] I have to say that this TV has dulled the appeal. The reason for the soundbar was due to the onboard speakers failing [not the first to report this on a slim 'LED' TV with this [or other brands] for sure and the soundbar appeared to offer the best solution; even though my question relates to maximum sound output it's just a general family TV which is set mid-range most of the time.
The other problem was that [just a few months out of warranty ... I can buy a car with 5 year warranty but the TV just has 1 year!?!?] ... the top five inches of the screen went into 'pixelmania' and we could only watch cinema profile with a light-show across the top. Our supplier [fully accredited by Samsung] said "not our problem, we will talk to Samsung" the response we were given was "Samsung say out of warranty". They [the supplier] did offer "the only possible solution" of "a new screen panel" for something like $550. We simply watched our [other brand] TV for a while and surprisingly the Samsung partially healed itself ... praise be. We do still have a line across the screen where the 'pixelmania' ended but it's watch-able; we have a lot of Samsung products but also had a lot of Sony products before they lost the plot some time back.

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