Karl has been doing some mapping work on my car laterly and has found this fault?????????????????

The limiter on the chip has been set above 7000rpm but when the car hits exactly 6450 rpm it feels like it has hit the limiter and dies..Karl said it is like a Hard cut..

Now it may be a fault with the ECU which i am hoping it is,or, it could be a loom fault,interferiance????????

Anyone else ever suffered from this??

To tell you the truth it doesnt really bother me as i dont rev the car that hard anyway but it is just annoying now i know its there