Assuming your system is set up properly (im sure it is) how long have you had this equipment? It takes roughly 100 hours of burn in time before things open up and sound right.Try not to jump to worse case conclusions right away, its probably something simple. MM's like to have the correct capacitance set, so make sure you include the cables capacitance too, this can be 50pf or as high as 250pf! try and keep cable short (2 ft) to reduce this.
Matt M
Matt M