Unwanted limiting artifact in Audition 1.5 and 3.0 from a Lynx L22 Sound card

I just upgraded my rock solid Win XP machine with Lynx 1 sound card that ran AA 1.5 flawlessy for 10+years.

I now have a new ASUS  Mobo Win 7 machine running a new Lynx L22 PCI card.  Now all recordings via AA1.5 and 3.0 have apparent limiting at aprox -3db.The signal will go no higher than that and all recorded tracks have a square top wave form.

Lynx tech support blamed AA 1.5 and WDM drivers, so we tried AA 3.0 and had the same problem. As an additional test Lynx support had me record with Reaper using AISO drivers and there was no limiting artifac--so Lynx support is saying its an Adobe issue.

Any thoughts?

Thanks