Jheyson,
I may be experiencing the same revving issue at speed that you have, but I have not found a solution to the issue yet.

I have found that it happens at just about 26-27 mph. What happens is that sometimes (not always), when I hit that speed, it feels like it misses a shift point, and stays in a lower gear when it should actually have shifted into a higher gear. I end up with the engine revving high if I hit the gas, and I usually have to back off the gas, let it settle for a couple seconds, get down below 26 mph. Then, it usally will shift correctly into the higher gear that it seemed to have missed the first time around.

Does that sound like what you are experiencing?