Dreamcast laser acting weird on certain games.

I have a question regarding my Dreamcast.

Not too long ago I opened up my Dreamcast to lube the GD-Roms rails and such and while it has helped that terrible grinding noise found in most Dreamcasts I've noticed some weird behavior in certain games.

While playing certain games like Dead or Alive 2 and Soul Calibur the laser assembly constantly moves back and forth really quickly while in game. The game itself loads and runs fine, so I'm confused on why its acting so weird. Did it always do this and for some reason lubing up the gears makes the sound more apparent? When I play my other Dreamcast games the laser doesn't do this, so I'm really confused on what is going on. If anyone could help I would really appreciate it, thanks.

Below is a quick video I shot so you can hear what I'm talking about. The game running is Soul Calibur.

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is it a backup

 

No, retail copy.