Also... when getting error -22 on IB MC join it means that the join request sent by the server didn't go through to the SM or didn't get answered for some reason.
From my experience, every network would have some -22s out there; especially when the server comes up. later on you could have ocation once. the driver will attemp to join again later on - no worries.
if your errors are accessive, then you should worry. if those are sporadic and/or isolated to the area where the driver loaded, don't sweat (unless you can clearly see that the specific MC group you are trying to join fails repeatedly)