@yifanlu: When we want to start it at boot, the cleanest way to play nice with Amazon's volumd that I found was to start it *after* volumd, and before the framework (And not in rcS like it was done at some point, or in the range the fonts & ss hack use early in rc6 (for no good reason, AFAIK, it wouldn't hurt them to run a bit later in rc6)). If it's started before volumd, weird stuff happens (nothing exported over usb, stuck on the connected to computer screen, etc). AFAICT, Duokan does some tricky stuff to deal with that issue, but this seemed simpler and cleaner ^^.
Short answer: just before the framework would be good

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