Basecamp will run slowly with Big Sur.

This is not a solution (Garmin have to update BaseCamp), but a short term workaround -

The problem (Mac running slowly) comes when you're viewing the maps in 2d, but not if you view it in 3D.

To get around it in the meantime -

1. Start Basecamp

2. Click on View > View 3d Map Only

3. Plug in your GPS unit and let the maps be read 

4. By viewing them in 3d it gets around the problem


Fingers crossed Garmin get it sorted soon.



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