It seems you have an aftermarket amp and have yet to hear your system since installing the amp. Depending on how you've set your amp gains may be the issue as well. You can adjust the gong a bit (between -4 and +4 if I recall correctly) under some setting on the head unit but that doesn't help much. Music, phone and navigation (I'm not sure about navigation as I don't have it) volume can be adjusted by the volume knob while the gong volume is mostly fixed, so if your amp gains are set too high the head unit puts out the gong at it's standard level but your aftermarket amp amplifies it to a ridiculous level. Your music, phone or navigation isn't as loud because you can simply turn down the volume for those. You need to make sure you've set your amp gains with the head unit set at its maximum undistorted level, which is around 51 clicks of the knob. It helps to use test tones. I'm not familiar with the Cleansweep (like if it as a user-adjustable gain/volume), so I'm not sure how it'll affect this.
'11.5 M3 sedan | Jerez Black Metallic | 6MT | M Performance Exhaust | no DCT no EDC no NAV no nonsense