I feel you, it's hard to find the perfect hardware. maybe you should consider building your own device with an arduino + dmx shield
as why is dmx over ethernet better thanks usb, just a few points :
- it does usually gets its own power supply (so it will never stop. usb/dmx devices can stop if too much usb devices are plugged to one source and result with a blackout)
- you can use it thru a network
- it doesn't need any usb driver / library (it's network so it's compatible with most computer / os. no problem. everyone is struggling right now with el capitan and usb dmx pro...)
my advice : if you need to invest to an ethernet device : go for dmxking, you won't regret it (for example, if your computer crash, the device will keep the last state until you reboot it and feed it with dmx, enttec ode : nope)
regarding the size of your kit : I'm sure you can manage to include a poe router in it.
regarding a hub with poe / usb / etc. : I wouldn't trust any kind of hub like that anyway. I rather focus on keeping my audio / video / dmx signal as clean and reliable as possible. even if I need to purchase a bigger pelicase. I don't like to worry about hardware.
I hope you'll find the perfect kit for your need. keep me posted about your decision
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