is this a known 10.6 issue? something in setup? I ran the test on my computer and it says I should be have the correct hardware.
Can you start a new project and re-add the basemap you used without issue?
I tried a new mxd and it still locks up with basemap (streets)
Well then that narrows it down to your machine or your locale.
You might want to contact Tech Support
I forgot about this.... check it first
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