I had this on scale changes.

Either the OS or map disc have an read error, make sure that the blank discs are of a good make and that you burn at either x1 speed or the slowest rated speed of the discs.

This fixed mine and I'm now stable.

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Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.