I tried multiple options to increase volume. I use Samsung UHD 4k 49 inch Samssung Smart TV. Once i tried with my friends BOSE old blutooth speaker with this TV and was working fine. then after i tried with my Bose Revolve speaker, i was also working. Suddenly low volume issue coming again from 3-4 days. Its not recovered after updated its firmware3.0. while its working fine with My Android MotoOne and MotoG phone from day one.
I called to Samsung customercare and they are not responded with positive answer. They just said that their customer raised only not working with bluetooth. never complaint about low/loud volume.