I really need some help here regarding my hashrate. I am not getting what is claimed with my 750 Tis

Cayars has very kindly proposed his help but was unable to this date to connect to my rig. Any other devs out here who would have time to help me out please?

Here is my issue. On whichever miner I use be it ccminer or nvminer I get lower hashrates than expected. For example on x11 I get ~2.300 Kh instead of the ~2.600Kh claimed. On dmd-gr I get ~7.000 Kh instead of the 7.800 Kh claimed. So one and so forth.

I am on Win 7 64x. Currently running nvMiner (v1.2U-D7b - 29-07-2014) with latest drivers 340.52. I had the same issue with previous beta drivers 340.43 and also previous miner versions, so it doesn't seem a driver related issue.

Thanks for any help.