PS Audio PWT and PWD MK II--recent acquisiton

I began a discussion of HDMI cables for I2S under the Cables heading, but my observations and questions about the PWT and PWD MK II are more appropriate here, I think. Having had some time to put this combination through its paces in my system (Modwright KWI-200 integrated, Proac Response D-2 speakers, Rel S-2 sub, Analysis Plus Big Silver Oval speaker cables, Clarus Aqua XLRs, Pangea HDMI) I'm not very happy with what I'm hearing. Yes, the two digital sources (DAC & transport) produce impressive resolution, spatial sense, and detail, but in a way that strikes me as very unmusical. In fact, though there's no discernible "glare" in the sound, it is extremely piercing and seems like it could damage my hearing if I listen too long at even reasonable volumes. 

My Cambridge Audio CXU universal player is much more pleasant to listen to even if it doesn't quite match the hyper-resolution of the PWT. I have a Wyred4Sound reclocker inserted between the CA player and the DAC, connected with Audioquest Carbon coax cables. This produces a much more musical presentation.

I'm open to suggestion here, though. Anybody experienced this, and can you suggest a remedy? My first inclination is just to sell off the PWT as a failed experiment.
are all components plugged into a single point?

if so, does it have MOS or any other devices in it?  or is it a simple set of connectors, like some Tripp-Lite strips?
and what is upstream of that?  how configured?

what else changed when the harshness appeared?

is the APC an isolation transformer?  I don't see much about its method of operation.  if so, what is the interwinding capacitance?
Here is a link to what information I can find about the APC unit I have:

What I know of what's upstream of that is sketchy--it's on a dedicated 20-amp circuit that terminates at a standard (not GFI) breaker. The power chord I'm using is something of a mystery--it's an upgrade from the original that was given to me by a dealer from whom I bought a previous integrated amp, but I'm not sure who made it.

What I'm hearing I would not describe as harshness, I'd describe it as shrillness. Everything is absolutely crystal clear, it's just not pleasant to listen to, and it's been presenting this way since the very first note of music that came out of it. Since the CA CXU is so much more musical (if a little less resolving) through the PWD II, I think the issue is the synergy of the transport and my amp/speaker combination. I'm still open to opinions and suggestions though.
Is the PWD MK2 equipped with the bridge? Either way, set it to Native or Native X (with the bridge installed), this will ensure there's no up-sampling and set the filter to auto. I personally found the PWD MK2 with the bridge installed to be a very musical/natural sounding dac. The detail/resolution is there, but that's desirable. The volume should also be set very high (100%), and the actual volume should be controlled by your integrated.
Doesn't have the bridge, and I do have it set to NativeX. Generally, I'm using PS Audio's suggestion to use Filter 1, but I've tried pretty much every setting and the differences, while discernible, are not major. I have the volume set to 95, but I'll try it all the way up to 100. Additionally, I have also tried connecting the DAC to my amp bypassing its pre-amp stage and using the PWD II as the preamp. It's actually worse that way.
I loooove my PWDII, though I use it with the Bridge II instead of the PWT.  Into my integrated, I find the sweetest spot on the volume control between 70 and 78.  NativeX and Auto filter.  Make sure you've updated the firmware to the latest.

Mine's far, far from shrill.  Keep tweaking and you just might be rewarded.
Thanks for the suggestion--I've now broached the subject on the PS Audio site's community forum. We'll see...
Reinstall the firmware. If you're not using the Bridge, try another firmware version (2.4.5, for example). I once had distortion issues that were remedied by simply reinstalling firmware.
If you're not using the bridge, I'd "downgrade" to the 2.0.2 (from 2011).  I always liked that one the best for the standard inputs.  If you want to try it, send me an e-mail (2.2.0 is the oldest one on their website I could find).  I thought it was smoother than subsequent upgrades and eventually quit trying new firmware.  I had to upgrade the firmware to use the Bridge II, but the bonuses of Ethernet audio overcame what I thought of (like you) as a shriller, less natural sound. 
After experimenting with different firmware versions (with particular thanks to cal3713 for sending me the 2.0.2 version, even though I haven't been able to get it to work), I do notice some differences but they're small and still haven't quite solved the problem. I'm really on the fence about whether a major upgrade of HDMI cable would do any good, but I might consider a significant power cable upgrade. I did this for my Modwright integrated--an Anticables Level 3 Reference--and it improved things noticeably. I've read that these PS Audio units are rather sensitive to cabling.
Short update: neither version 2.02 nor 2.03 seem to work for the PWDII, as they result in a blank screen display. I'd still like to hear one or another of these sounds, however. Any suggestions?
 2.0.2 and 2.03 firmware are not compatible with later PWDII builds  such as mine and most likely yours too. 
Further adventures: trying out different firmware versions, and yes there are slight differences between a few of them, I’ve settled on the latest for both the PWT and PWDII. Sorry I won’t get to hear the earlier versions but as bsme85 points out, they’re not compatible with my DAC.

The issue of shrillness is not really solved, but having done some extensive comparisons between the PWT and my Cambridge Audio CXU, it would be a noticeable step backwards to rely on the latter for my CDs because the image, detail, and resolution of the PWT are so compelling that it would be like going back to high school after completing a graduate degree. Regardless of how much fun you had in high school (I didn’t, but that’s a different story) you wouldn’t want to go back, having graduated and moved on.

I’m pretty sure a speaker transplant would give me what I want, but where to go from the Proacs? They’re very appealing speakers, if a little forward and bright.
Dynaudio C20s, Totem Model 1 Signatures if you can find a pair, Dynaudio Special 40s, or any model from Legacy Audio in your budget, however they use AMT tweeters and I'm not sure how you'll find them. I think your main issue may be you just aren't used to such detail, and of course the Proacs may be a bit bright.
Thanks for your suggestions, nitewulf. It appears (from my internet research anyway) that the speakers you suggest (with the possible exception of the Totems) are all extremely accurate but rather clinical in their presentation. I've heard Dynaudio speakers in the past and found them rather uninvolving. I was, however, impressed by a pair of Totem Element Fires a dealer let me audition. Same dealer demoed a pair of Sonus Faber Olympica 1s that I liked, but how they'd sound in my system I'm not sure. Anyway, new, these speakers are out of my price range.

Tying back in to the main subject of this thread, it may be that very resolving, matter-of-fact speakers would be what the PWT/PWDII combination respond to best, but this will take some experimenting. It's just the upper frequencies (probably up in the tweeter range, like 2Khz and above) that give this shrill edge. Below that, I love what I'm hearing.
Thanks for the suggestions. There are some dealers within driving distance who represent these brands, so when I have the time, I'll give these a listen. My only experience with Vienna Acoustics was over 15 years ago when Magnolia (adjunct of Best Buy) was selling them. They didn't quite do it for me then, but I'm sure they've evolved in the interim. I could be wrong about this, but I always equate Spendors with Harbeths, and I have auditioned the latter but they're not my cup of tea either.
You might look for speakers with a scanspeak soft dome tweeter.  I have Coincident Super Eclipse IIIs and have always loved how they sounded with my DAC.
Another update: The transport has been serviced twice by PS Audio (both were covered under warranty), the first time to address an issue with the transport mechanism itself which was unduly noisy, and the second time to address an issue with occasional freezing. This last issue is not uncommon, I gather from reading other threads here and in PS Audio's forum, and when I sent the unit back to them I also mentioned the fact that I thought the sound might not be all I'd hoped. They repaired a problem with the power supply and upon its return, it's like a different machine entirely. NOW I see why people are so taken with the combination of PWT and PWD II. Two further upgrades have also helped make this quantum leap: a Transparent Audio HDMI cable for the I2S connection (this makes a minor difference), and an Audience PowerChord SE that I'm using for the DAC, which is a night-and-day improvement from the previous (Cullen) cable. I'm really liking what I'm hearing now and I'm going to stay with this for the foreseeable future. Coming soon: a new power chord for the transport, too, which I hope will improve things even more.

A short word about speakers, since the subject was broached here: I still really like my ProAcs but I do hear some limitations in their presentation. I've auditioned a pair of Ryan r610s at a local dealer and was very impressed with them. I'm tempted...
Whether or not HDMI cables make a difference is pretty controversial. In this case the cable is transmitting only audio data using the I2S protocol, so it's possible that the improved materials in the Transparent cable do a better job of moving the bits, analogous, perhaps, to what happens when you upgrade your coax-digital cables. Just a theory, this. To my ears the difference was small, and I haven't really done enough A/B testing to confirm this. It might just be placebo effect. The power chord, though, that was a VERY noticeable difference.
I'm not an audio engineer by any stretch, so I don't have deep knowledge of the science behind any of this. Only know what my ears tell me.