It took me a while to figure this issue out, as I finally saw it for myself recently. The problem seems to be related to the newer "Overlay Aspect Fix" feature.
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FIX!
If you see the "Slow Motion" text at the bottom, the fix is easy!
Simply open the BAM menu (~ or Q), then goto REDEFINE KEYS. Then under "Overlay Aspect Fix" assign any key not being used (like O).
The problem should go away immediately. Close the BAM menu with ~ or Q. Close FP and reload the table to confirm the problem is still gone. If it is gone, then you can go back to REDEFINE KEYS and choose Reset to Defaults to remove the key assignment.
This only needs to be done once, as it gets save to the BAM.cfg file.
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The latest BAM update included with FP and BAM Essentials AIO 3.5 or higher seems to have fixed this issue... BUT... if you see this problem again, then just do the same fix I outlined above.