Szia Miditom!
Találtam valamit az echoaudio honlapján, ami összecseng azzal, amit Te emlitettél( ezek a kártyák is motorola DSP-t használnak):
www.echoaudio.com

AMD ATHLON USERS
There have been reports of compatibility problems when using an Echo Digital audio card with AMD ATHLON processors. Echo, AMD, and Motorola have joined together in trying to determine the cause of these compatibility issues. It appears that the problems are related to the Motorola DSP that we use in our products and certain Athlon motherboard chipsets and not the Athlon processor itself. There is a new Athlon chipset from VIA (the Apollo KX133 or KT133) that works well with our products. This chipset is now available on motherboards from numerous manufacturers. Click the link below to get a list of manufacturers from the VIA web site. (http://www.via.com.tw/support/partnerskx133.htm ) This goes for the AMD Thunderbird as well. We recommend Athlon and Thunderbird just as much as Intel as long as you follow the information above. The only brand board that we may have a problem with is ABIT. We are looking into this.