Having an infected batch sucks. Been there. Twice. In a row. One batch turned to vinegar, the other produced volcanoes of foam. It really shook my confidence in brewing, but I decided to go crazy with sanitizing and it paid off. I discovered that plastic items were the most susceptible to germs. It was a learning experience for me.
Replace those plastic spigots from bottling buckets--gaskets and all. Replace plastic tubing. Those are notorious infection points, difficult to sanitize, but cheap to replace. If plastic fermenter and bottling buckets are getting scratched up inside, replace those, too. Go to the home center store and buy one of those long plastic trays for wallpaper jobs. Fill with Starsan and soak autosiphons, bottle filling tubes, etc. Consider spending the $$ on silicone tubing to replace the cheap vinyl stuff. Silicone can withstand heat and you can boil it.