I have a similar problem with my LG 27LQ600S-W. LG omitted a 3.5 headphone jack on this model and the TV speakers are really poor, I mean really, really poor. They sound like a tinney1960s transistor radio. I have a nice set of Phillips powered PC speakers that I used on the TV I replaced with the new LG. To work around the "no 3.5 jack" problem, I bought an optical to analog converter with a 3.5 jack. When powering the TV on, I have to go to settings>sound out opptical>select device>and then select the ID of the converter, confirming "yes".
Every time I power on the TV, I have to go through this tedious ritual. I can't make the choice "stick". Will a Bluetooth adaptor with a 3.5 jack maintain the choice when powering up the TV?
Any suggestions are appreciated, thanks