Blade cuts during playback

Instead of making blade cuts "on the fly", set Markers instead (just type the M key as you play).

Once you have all the markers set, set the Tool to Blade, hold down the N key (or type the N key to turn on snapping) if it is not on and skim through and blade at all the markers. With snapping on, the edit point for Blade will snap to the marker.

Somebody else might have a better suggestion...

If you type the spacebar to stop playback at the point you need to blade, then blade, then restart playback with the spacebar, you **shouldn't** lose the waveform so, although you need to hit the spacebar a couple of times for each blade, it shouldn't slow you down quite as much.

Unfortunately, FCP's waveform recalculation during blade cuts is a known issue, and there isn't a direct solution to turn off the recalculation. However, there are some ways to speed up the waveform redrawing, such as:

• Increasing the cache size in the Playback preferences, so FCP can store more of the audio waveform in memory, reducing the time it takes to redraw it.
• Purging the cache by using the "Edit > Purge > Audio Render Files" option, freeing up memory that can be used for redrawing the waveform.
• Working with lower-resolution audio, as the waveform redrawing process is less intensive.

It is worth noting that while these options may improve the waveform redrawing process, it is not possible to eliminate it completely.

This shouldn't be an issue on a silicon MBP, but maybe you've got too much on the timeline to keep up. Have you tried using proxy files or lower resolution on the timeline just to see if the forgoing could be the issue?

You might want to check the Command Post utility. It may have a function that enables constant waveform recalculation during playback. FCP suppresses it to improve playback. The constant recalculation might cause dropped frames depending on your system and media.

Perhaps zooming in further so that there is less information in the waveform to redraw will help as well?

You may want to try CommandPost.

It is a free utility that adds extra functionality and among the things it can do is to change FCP hidden preferences, to redraw waveforms during playback.