Mine was a 'new' device, on installation and set up the latest software
update was applied. Not only was there audiio stuttering (PCM and Dolby
Digital+) there was also brief flashing in the video (menus) and it
couldn't really make up its mind with ...
Stop guessing what the problem is. Go back to the developers get them to
recreate (should be easy) the problem and fix it. This release is
appaling and not fit for purpose.