Well, I have a Zen Touch 20GB, which I would assume is exactly the same other than price and storage space.
On mine I am not sure if it really has 24 hours (I've never actually tested the exact power), but I usually only have to charge it once or twice a week and I use it quite a bit.
As for the line out, I've never really attempted this and I'm not sure if it has it. It does not have another jack for line out, but I would assume that you could use it to plug in from the headphone jack if you had the right cable.
Hope this helps!
Does the Zen Touch 40GB have a line out (to connect to a boombox)?
Is the battery life really 24 hours?
Thanks!!!

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