... almost forgot to mention another important factor...

make sure gain levels are carefully matched for all items of equipment
in recording chain
to keep noise floor at most optimum..

A simple illustration, my mum is 80 and phoned up distressed that her telly had developed a horrible hum
and she could no longer hear the dialogue in Coronation Street.

I got a train to visit her asap expecting at worse the price of a new TV.

Long time examining her TV and arial setup later,
I discovered the cause of the problem...

She'd set the volume level on her Freeview box at minimum
and was compensating by turning her TV volume to maximum.
Thus amplifying all the circuit & interference hum from the freeview box to intolerable levels.

I explained that she needs to set the freeview box to max
and only control volume levels with the TV remote control for best noise free listening...

She still gets it mixed up and I have to sort it out every time I see her.
But at least I know what the problem is.