Having the same problem streaming from Synology 218+ to Android TV Philips 55oled903/12.
Dropping frames when new subtitle line appears. Very annoying.
VLC for Android TV 3.3.1 so no fix has been done yet.
Hello, I have the same issue.. 4K movie files hosted on Synology NAS, playing with AndroidTV on Philips 55OLED903/12 TV. If the subtitles are activated frames are dropped on many subtitle lines.