I've got a Blackbird and it is very sensitive to VTA; however, your adjustment and the resulting unsteady sound makes me thing that something happened in the move.
Use canned air to blow out the cartridge. Don't put the nozzle too close because the parts are sensitive, but see if that doesn't help. If that's no good, then completely dismount it and inspect it with a magnifying glass. If all appears ok, then try to remount it one last time. Be careful not to overtorgue the machine bolts holding it to the arm or headshell.
Try a cheap MM cartridge in the arm to make sure that the arm is ok. There could be some binding that you don't feel, but I really doubt this possibility.
Dave
Use canned air to blow out the cartridge. Don't put the nozzle too close because the parts are sensitive, but see if that doesn't help. If that's no good, then completely dismount it and inspect it with a magnifying glass. If all appears ok, then try to remount it one last time. Be careful not to overtorgue the machine bolts holding it to the arm or headshell.
Try a cheap MM cartridge in the arm to make sure that the arm is ok. There could be some binding that you don't feel, but I really doubt this possibility.
Dave