Yup. As I recall, Tomshardware did a test of both and the digifire actually had appreciably worse quality on the surround channels (?) due to interference or some such.
edit: here it is:
Toms notes:
QUOTE
"In the objective RMAA tests, this quality difference of Fortissimo III 7.1 and Digifire 7.1 was blatantly obvious. It was definitely noticeable in the bandwidth and appalling when it came to stereo crosstalk. This, by the way, is a measure of the isolation between the card's left and right sound channels, in other words the highest level of sound that can be heard on a channel before it starts to be heard on the other as well. This is an important factor in multi-channel environments."
And later explains that a driver fix may solve certain problems....