Hi movie fans and audiofiles | Modification of Panasonic UB9000 blu-ray player

I am here to get more Info about modifications of blu-ray player. I have Panasonic UB9000 with ESS chip and Rattlebyte multiregion mod bought in UK from TPS. I like it, it allow me to use external subtitles and I can watch special features on discs from KL (USA) without any problems. I wish I could get the sound quality on the next level as I would like to play more Dolby Atmos and 5.1 Audio Blu-rays. Anyone have tried to upgrade the player with mods from Coris or another sources like oppomod or Authentic Cinema?