This may seems like crazy advice, but I would contact several dog trainers online or in your area...and ask for help. There may be a reason your dog is doing this....and the cure may be simple.
I liken this to working with my teenagers....whoever understands why the do the things they do...but when you ask another Mother whom has been there...or a professional...knowledge is power....and bam...you find out that dogs and teenagers do have reasons why they do things.
lol Hope you find the answer, and let us hear from you when you do find out!