I spent ages pushing to go faster and faster and just kept damaging myself, so it was completely counter-productive. I may even decide to stick at around 30 minutes in future. Better to be able to go 5 times a week than push so hard you're needing more rest days.
I've never used the inbuilt speakers - I jury-rigged an old amplifier and speakers with a cheap bluetooth connection so I can blast music as loudly as I like. The inbuilt fan is a bit silly, though.
I can never manage to concentrate on a book or podcast while I'm running. i just feed off loud guitars.