My Meridian G08 doesnt as good as i thought ...

I bought a meridian g08 after listening(also the positive user posts here) to the amazing Meridian 588. but 588 lows didnt sound right, so i went ahead and bought the G08, but to my dissappointment the mids and highs doesnt doesnt as good as 588. but the lows are pretty good. I am very dissappointed by this purchase, when i try to do a A-B comparison between my Toshiba SD9200+CAL Audio Sigma DAC combo, G08 is only better by a very small margin. I called up meridian to see if they might have defective parts, but the answer was it either works or doesnt work. i also tried upgrading to the firmware that is on the merdian site, but no use. It is a used one so there is no question of not being broken in.

i am trying all the gimmicks, different interconnects and isolation tweaks using cerabal

Does anyone have insight on the issue ?

thanks in advance