What is this noise?

For the second time in 15 months of ownership Garmin are proposing to replace my Neo bike, for the second time a strange noise is coming from the bike when pedalling and only when the bike has warmed up. Anyone know what it could be and if there is an easy fix without the hassle of a full replacement?

See video

Thanks

    • My crank was loose at first, as was the case with others here in the forum. I received a new screw from Tacx and fixed it.
    • Recently I've had the same noise as in the video. Sometimes the crank turns completely at the start and has no resistance or can display watts. I have to briefly turn the flywheel at the back and pedal at the same time and then the resistance comes back again. The noise comes and goes during training. Sometimes it makes a loud crack and then it's gone. I'm worried that at some point the crank will stop working.