Trying to clean vintage kettle (again!)

Posted this a week ago but I still haven't solved this problem and I'm not sure where else to ask.. Basically I have a vintage stainless steel kettle that came with a 1970 Goblin teasmade and it has a weird smell/taste that i cannot for the life of me remove. So far I have tried boiling it with white vinegar and letting it soak for 24hrs (twice), letting it soak with baking soda and lemon juice (did the baking soda twice too), boiling water over and over, cleaning it with a descaling solution, scrubbing it and shaking it with ice and salt. It STILL smells gross. I'm wondering: 1. Why does it smell so strong? It's not caused by the previous owners as it's definitely a kind of chemically metallic odour 2. Should I give up or will persistence work?I haven't tried a couple of the suggestions I got from posting this last week which are Zeolite chips and cleaning it with alcohol, but something tells me that if white vinegar can't get rid of a bad smell, alcohol and rocks won't either.