What OS and what version of Ps and ACR?
What printer and printer-paper profile?
Can you post a screenshot of the problem - for example, open a TIFF/PSD, or whatever, of a previously converted raw file that prints properly and soft-proof it in the appropriate printer-paper profile in PS; then open that same raw file in the newest version of ACR that you are having trouble with, do a new conversion into PS, and set up soft-proofing to be identical to the older conversion. The only difference between the two images should be the version of ACR that did the conversion (i.e., all conversion settings and the color space into which you convert should be identical, all of the soft-proof settings should be identical, etc.). View them 2-up, side-by-side in PS and take a screen shot to show the effect you are describing.
I assume you are talking about the soft-proof in the regular PS window, as opposed to the printer dialog. The soft-proof in the printer dialog has been inaccurate for several versions of PS, at least on my Macs (i.e., it appears desaturated and grayish and, when set to the identical soft-proof settings as in the regular PS window, it looks completely different than the PS soft-proof).
It is a little difficult to visualize the issue you are describing otherwise.
kirk