Are you creating internal DPSK on vSZ and using it right away? I just want to make sure that you are giving some time to vSZ to propagate the changes.
Try NOT to modify the VLAN on the DPSK and check if you still see the issue.
If issue is reproducible at will, please open a support case with all the details from the below link and they will check it.https://support.ruckuswireless.com/cases/new
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