Converters and Garbage mixes?!?!

[mistaD]

First i want to appologize for the lengthy post but im really in a rut! Also shouts out to everyone who contributes on this forum as i've been reading on here for a while and have learned more in months here then years of books and classes!

I upgraded my studio from a Yamaha dsp2416 card and a Mindprint Envoice to a RME Multiface and Mindprint DTC and my monitoring setup from an old Kenwood amp with JBL bookshelf speakers to Yamaha NS-10M'S and a samson reference amp. I used to use the spdif out from the DI-mod of the envocie into the yamaha dsp and was pleased with the results i was getting, i had quite a few mixes playing on local comercial radio! Heres the thing though.... now with the upgrade my mixes sound like garbage! They sound great through my monitor setup( Yamaha NS-10M's & Samson studio amp) but completly different when i burn a disc and play it on a home system or a car stereo. Now The high end sounds sterile and weak with an annoying crisp even on dry tracks(no eq) especially on precussion like Congas,Cymbals and Claps! My low end is still good if not a bit too much. With the Yamaha what i mixed and what i burnt were exactly the same! So i have a few questions!

1. Right now i use the spdif in/out from the DI-mod on my DTC! So i guess im bypassing the RME Multifaces converters? Would i be better off using the converters on the Multiface rather then the DTC?

2. Today for the first time i moved from 44.1 khz to 96khz and noticed that the same sterility and weak sounds that were showing up on my home system were now more evident on my monitoring system! Does this mean i'd be better suited to record and monitor in 24/96khz?

3. Is this just what good converters sound like.... are they just too clean and was it the color of the Yamaha Dsp card in cunjunction with the dirt and warmth of the enovices tube that i was hearing?

4. The only other changes that were made were i started triggering my samples from Battery and Kontakt rather then my Akai S2000 and i use a lot more VSTI'S in place of my Korg Trinity. Are the same samples that used to be warm through my Akai now sterile because of the software synths/Samplers? Even though I still route them through My DTC to warm them back up!

5. Or is this just a bad monitoring setup wtih bad room accoustics thats throwing off my mixes? Does anyone have any links to other threads or sites that can assist in treating my room?

I honestly feel like i have to learn how to mix all over again because what i was used to hearing on the crappy kenwood amp and JBL bookshelf speakers is completly different then what im getting with my new setup but it was translating bettter to other systems then my mixes do now! Any help would be greatly appreciated guys!