To the best of my knowledge, all Bluetooth audio codecs have latency that is audible in the form of lip-sync or delayed special effect (of games and movies). apx has developed a special codec called aptxLL to handle these applications, LL stands for Low Latency. The aptxLL is flxed at 16Bit/44.1kHz, not exactly an ideal codec for hi-res audio application. In fact, even aptxHD is limited to 24Bit/48kHz, so Cayin decided to opt for LDAC instead of the Qualcomm solution which require additional Qualcomm hardware.
In fact, audio sync. has always been a problem with bluetooth and outboard DAC/soundcard or AV processor, that's why most video player app offers audio sync adjustment to solve the sync problem. I have that problem too with my home audio system when I connect my PC to a Yamaha AV center (or Bluetooth headphone if that matters), but I can fine tune the audio sync. to match lip syn or special effect such as gun fire in movies. My Yamaha AV center offer similar setting but they are less user friendly. Unfortunately Youtube didn't offer similar settings, at least not that I am aware of.