Odd shifting

[batshapedheart]

So my automatic Boxster has started shifting rather oddly. It waits for higher RPMs to make the shift, stays longer on 4th and even if I'm at 5th at 40-50 mph it suddenly decides to drop the gear to 4th again. To my knowledge no one has touched the ECU, except MAYBE when it got a tranny rebuild last May, but the odd shifting hasn't started until the last few weeks.

Ideas?

[Timco]

Fluid condition? Fluid level?

Last May? Should be some warranty still. I would start there before you touch it.