This is the oft repeated question on playing audio via bluetooth on RPi. There are too many posts out there, but most of them are dated or do not apply to the stretch version of raspbian and hence asking this question again.
I am on RPiv3 Model B with Raspbian stretch. I am able to connect to my bluetooth speakers successfully. When i try to play something to it using OMXPlayer or MPG123, there is no error, but i cannot hear any sound. I have checked to ensure that the speaker is working properly by connecting from my mobile. Also, when i play via headphone jack it seems to play properly.
Both OMXPlayer and mpg123 seem to diregard the
-o alsa command to run on bluetooth. I have tried various options and nothing seems to work.