I'll order 2 together with clamps and start with them and see what difference they make. Hopefully it will sort the problem. I really appreciate you help with this as I may be able to wield a hot soldering rod but I'm certainly no hot electronics whizz! But I am learning with the help of the likes of yourself. Many thanks!
Pic of the Truvox in its case.
https://www.vintage-radio.net/forum/...pictureid=4508