As mentioned above by @guyaguy... this is a gain staging exercise.
You can probably just turn down the Individual Osc mix levels further... I've got several paraphonic patches where I'm down near 50-60% volume for Osc 1/2/3 mix levels. I have noticed that in paraphonic patches I almost always turn down osc mix levels... (I'm guessing that in standard mode / non-paraphonic mode, there might be a little bit of attenuation added to the other oscillators when you turn up others... and this attenuation is not present in paraphonic mode) - not sure if that's correct, but I wouldn't be surprised if that's the case.
Also check your other sources going into the filter. If Ext In is turned up that will be adding natural feedback that can overdrive the filter. And of course check Filter Drive, Tuned Feedback and Distortion to make sure you're not unexpectedly getting those gain sources in your mix.
Some synths do all the gain staging work for you by attenuating parts of the mix based on parameters set, but this unit really gives you extensive control over the signal path and gain staging... for more advanced sound programming this type of setup is preferred because you can purposely push levels with various different methods... allowing for a wide variety of more aggressive tones, or just hitting the filter a bit hot for a slight overdrive.