I'm editing a short film shot on Sony XDCAM HD422 1080p25 (50mbs CBR).
I'm editing it all online off my Firewire 800 drive, and I keep seeing these flickering horizontal lines on playback. It's different from interlaced combing as it's more spread out.
It's less obvious when I render it out but it's still there.
Can anyone please tell me what this is and if it's a problem?
Make sure that the sequence settings match your 1080p 25 fps footage. If you're actually editing in an interlaced sequence you'll get the artifacts you're describing.
Does the playback look somewhat blurry as well as showing artifacts but becomes sharp when you stop playback? If it is then your RT settings are set to 'Dynamic' and FCP is lowering the quality during playback instead of dropping frames. This will also look like horizontal flicker. This may happen if your FW drive is not up to the demands of FCP's playback requirements.