True, but unless your careful a character with Visual, Audio & Smell enhancements all installed could easily start claiming 6, 9, 12+ dice on a general perception test stating each enhancement gives them a separate bonus.
Nah, we wouldn't. That's exactly the purpose of us asking: We get get told what sense it would be, and apply only the appropriate modifier. If the check is too generic, the GM either makes a call based on what sense he believes best applies, and then he tells us. If it is ultra-generic, he will tell us no sense would really be applicable, and we roll the base perception (which would only have modifiers from qualities, specializations, or magical sources, if any).
If two different senses apply, he'll tell us which two, and then we choose only one bonuse from gear (for example vision
or audio bonus). It's sort of a 'gentlemen's agreement' we came to back in SRM4, to prevent that very kind of cheese, much like our players not looting anything more than some ammo to replace what was used already.