Leo did this a while back.  Not sure which thread it was on but he then used a chromecast instead.

His description was pretty brief, not exactly a DIY: Follow the repair manual to dismantle, saw off & sand the mount, Sugru shut the connector hole.  I found it here: http://archivedforum2.beoworld.org/forums/t/21699.aspx

Thank you for the replies. I have just connected a Chromecast to my Essence MK1 and it works very well. I have bought another Chromecast and connected that to an BeoPlay A1 to test which is not brilliant as it times out and turns off. However, that was the plan with the BS8 and removing the dock would make it much neater. A power source from the dock to the Chromecast would be nice but I think that is expecting too much!

Chris Harrison wrote:

A power source from the dock to the Chromecast would be nice but I think that is expecting too much!

That isn't expecting too much.  It "should" be sending +5V to charge a newer USB iPod and +12V to charge an old FireWire iPod.  There are many dock connector pinouts on the Internet, plus there are pre-built cables with *female* 30-pin to *female* USB available for purchase if you're not sure of your technical skills.  It's not as neat as removing the dock and hiding the Chromecast inside, but you can easily get the power off the dock and wire audio out to the BS8 line-in.  Kinda dongle-y-looking though.