The Terrible Chewing!

I have a year old yellow lab. He is a Great Dog, but does have one huge issue! He chews everything! He has eaten a hole in the wall of the house, he eats the drywall and any exposed wood on cabinets, and last night he was given a new pad for his kennel and within 10 minutes he had it destroyed. Tucker is given ampel exercise (2- hour long 3.5 miles walks and 2- 20 minute jogs on the treadmill) He has a box full of rubber, rope, and chewy toys along with the full time companionship of a year old weimi. We have tried those "no chew" sprays, but to be completely honest I think he enjoys the taste. Does anyone have any other suggestions? Thanks

You've done everything right so far. It almost sounds like some kind of compulsive behavioral disorder.
   
Given the amount of exercise and toys your dog enjoys, he obviously has a low attention span and high energy. One thing that sometimes works when all else fails in such cases are Kong Biscuit Ball -type toys where there is a puzzle involved. I've seen dogs entertained for hours like this. Basically the toy has holes in it with biscuits inside and the dog must manoever it into specific positions in order to get the treat out. Any thoughts?