Short high drives

Driving me mad! I give my regular playing partner 6 shots, beat him 6&5 but he regularly drives 50 -70 yards past me cos he hits a low ball that gets some run even in these wet conditions while mine shoots up like an 8 iron and plugs where it lands, 200 yards if I'm lucky.
My 3 wood off the fairway goes lower and further but I want to sort out my driver as it's by far my main weakness.
It's a 12 degree offset Ben Sayers that is really straight, I hit loads of fairways with it, but 380yd par 4s are out of my range which is pathetic.
I would get a less lofted one but I beleive this is a fault that needs fixing.

The height of your drive will be affected by the loft of your driver, the steepness of your downswing, the position of the ball, the height the ball is teed, a slice or hook.

Please can you give a little more information on the above?

I come over the top a little, I think I'm probably too steep and I was prone to the odd slice hence the offset driver which has cured this - I use a silver/grey castle tee positioned level with my left heel.

OK. Try bringing the tee back a little, around an inch or two inside your left heel. In your downswing work on dropping the hands straight down so your right elbow gets to around waist height, keep your head behind the ball. release the club into the ball and try to keep the tee in the ground as the ball is swept away.

OK, thanks, I'll try that, incidentally I do knock the tee a long way in front of me usually.

Could be as simple as teeing the ball up too high. 12 degree is a lot of loft for a driver. Try try to purposely tee the ball what seems like too low for you. If the tee is flying way in front of you obviously you are making a lot of contact with it therefore going under the ball. A good tee shot would have the tee either still stuck in the ground or just grazed a little.

Actually Jamb I find that teeing a ball lower encourages a steep downswing creating a high shot.

Thanks for this tip Jamba, I did it today and it worked out incredibly. Gained an extra couple of rolls because of it.