I have isolated this to the type of plastic that is used in the kettle.
Our previous plastic kettle (Hinari) made an excellent cup of tea with no smell of chlorine or plastic.
Our new kettle (Tristar) is awful in this respect.
I have proved that it is nothing to do with the water. I have use filtered (Brita) and also mineral water in my new kettle and both water types do not solve the problem.
Boiling the water in a saucepan eliminates the bad taste and smell immediately
Solution : Buy an all-metal kettle (not so easy to find)
Dont ask me what type as I am just starting my search.
Happy hunting
Phil Collins