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See Thread called "Microphone Peripherals for 6g iPod Classic"

I emailed XtremeMac back in September 2007 asking if their Micromemo worked with the iPod Classic. They replied,
The MicroMemo for iPod with Video is compatible with the iPod Classic; however, there may be some functionality issues. These issues will not impede the ability to record.
Since then XtremeMac has discontinued the MicroMemo. I emailed them on 01/20/2008 and asked if it was still available (because it was no longer shown on their web site). They replied on 02/07/2008 as follows,
I'm afraid our current MicroMemo has been discontinued; however; our engineers are currently hard at work coming up with new products for the new iPods and iPhone. No information on a new MicroMemo have been released yet but it's very possible
 
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