If you're not getting a discrete graphics card for them, grab the A4.
None of the tasks you describe need the CPU advantage an Intel chip provides, whilst most of them benefit from having the superior GPU and drivers.
I would be gobsmacked if the A4 didn't do audio over HDMI. APU's are pretty muched aimed at the HTPC space....
In saying that, I don't have one here to test if they actually do or not.
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