Hooked up Shiit Mani incorrectly

I feel really stupid right now. I hooked up my Shiit Mani to my phono input on my Adcom GFA 555 preamp causing both my speakers to start distorting. Once I realized my mistake I shut the system down. I believe I may have damaged both my amps in the process.  Both amps are humming when turned on. What damage could of done? Any guidance would be greatly appreciated