Is this V5 RC ?
I've seen that once, when I tried a larger design, but when I checked a smaller design, that looked ok.
It may depend on design size, or on the 'degree of divergence' in the design.
One thing to try I guess, would be to use Import netlist, and then try "update from schematic"
With 'nothing to change', and a proven correct SCH-PCB, one hopes it is less likely to crash.