Why can't I 'play' the filter resonance?

[cl516]

I just got a TI.

I used to have the Virus C.

I remember on the 'C' I was able to play the resonance of the filter with keyfollow turned to maximum.

But if I do the same thing here on my TI, I get a very ugly sounding distortion, even though all settings in my distortion section are off.

Any ideas? This seems like a very basic patch that can be done on many synths.

Thanks!