After being given the 4 x 6' 30W LED fluorescent tube replacements
(and Non-starter fuses) I was extra aware of the now 'unnecessary
mains hum from the fitting.

This morning I by-passed the ballast (and took the cap out while I was
there), put the tube back in, turned the light back on and the hum was
still there?! ;-(

Undid the non-starter, hum stops?

The other tube in the other fitting also hums (or that could also be /
partly the ballast that is still in circuit).

Whoever removed the LED tubes and put them in the storage unit isn't
familiar with them and must have plonked them down on their end and I
noticed that the pins on the non 'input' end of the two I hadn't used
till today have been mostly pushed inside the partly broken end cap.
;-(

Luckily they don't need to be used so I'm going to remove them
completely and re-wire the fitting further to just retain the
non-starter and the one 'live end' (I don't think I need the pins to
be able to retain the tube in the fitting) and then I can try the
remaining two tubes and if they hum or not.

Anyone else noticed hum on LED replacement tubes? The only place I can
imagine it's coming from is any electronics in the (one?) 'active' end
cap and being amplified by the batten fitting?

Cheers, T i m