I must admit that i like that. Doesn't sound as super shrill/clean/whatever as some of the "top" soft synths. If it was for me, some devs could definitely roll off some of that top end.
Although Hydrasynth is definitely not as "muffled" as some older synths.
Actually... could it be that this synth aliases a bit? Definitely sounds a bit "dirty" in the high frequencies (which isn't bad at all).