Yes, I've had very similar problems.  I'd I suggest you try doing a reset/ reprogramming your DMD unit.  I've found that an inability to pivot in place is nearly always remedied by a simple reprogram of the DMD.

If for some reason, that doesn't fix it, I'd recommend the following:  1. Verify you have a fully charged battery (I know it sounds redundant, but I've had dead batteries give me fits, as I was certain the problem was elsewhere); 2, Verify your radio tx and rx are functioning correctly (I usually isolate the rx,  plug a fully charged 4.8v rx battery into the batt port on the rx, and then check each channel's operation using a spare servo); 3 Check your wires going to the motors from the DMD.  I've mixed them up before, and it does funny things to the tank; 4.  Lastly, take a DMD out of another tank (or a spare one if you've got it (I usually have a spare electronics set (MF and DMD) to troubleshoot problems) and see if the replacement works in the Tiger. 

If you don't have an extra set, then you Email Tamiya for authorization to send the DMD in for a diagnosis and repair.

Good luck!