Bad Speakers? Amp? or HU?

[adreano17]

i have 6.5 alpine component type s in the front, coaxials inthe back. problem is, my tweeters distort so much at curtain sound frequencies. before i get a diagnosis, they started when i first put them in at low volumes sometime. its crazy because sometime it will distort, sometime it wont. now this leaves me to think something is wrong with my RF 800a4 amp. gains are properly set, i wonder if the amp is slowly dying from this. thats my only explaination. it does it to all channels, and i seriously doubt alpine makes that much shit of speakers. i need some input.