Lip sync is always an issue when introducing ceiling speakers or simply not using the TV’s built-in speakers to render audio. Lip sync issues are caused when the audio device is able to render the audio much faster than the presentation device.
The P8-AD340 is a perfect solution to this problem with 20~ millisecond increments from its 16-way selector you can delay the audio from 20-340ms. Delay stereo audio with a simple L/R phono input and output connection.