The X5 model doesn't have AptX Low Latency codec as it is made mostly for sports where the video is not required.
The latency is a common issue for all Bluetooth devices without AptX Low Latency codec (can reach 0.5 - 2 seconds) and is not a product defect.
Please make sure that:
1. The earbuds are chosen as the main recipient of sound in tech settings on your source device.
2. The earbuds were paired correctly (first one earbud, then the next one).
Along with that, kindly try watching video from other devices and applications as sometimes such issues can occur while using some streaming apps on your device.
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