Reference this thread:
First thing to check if you run into this and use the reset switch on the 317 and that WON'T work, are you really resetting it? The reset pinhole is deep. The switch is way down in there. Make sure you're actually hitting it and don't just tap it, hold it 5 - 10 seconds.
Next up, this has happened to me twice in 24 hours. A new variable is I got one of the little L7 line-out docks and I'm using that. Recognizes and outputs through the dock fine, no problem, so I really doubt it's a defective dock. Another new variable is that before I got the dock and connected it to my desktop speakers, I wasn't leaving it connected to my 15-inch retina MacBook Pro when it was in sleep mode. I was disconnecting it. The two USB ports on the MP Pro are both high-power ports and they both stay hot in sleep mode -- they're powered all the time and can wake the laptop for data traffic. It's been my experience some rechargeable USB devices will drain power when connected to hot USB ports with the computer in question in sleep mode.
So, anyway, I'd been disconnecting the E17 if I was going to sleep the laptop for long. When I connected the L7 dock, I switched off the E17 when sleeping the MP Pro, but I left it connected. Also the MB Pro has a feature, it'll wake every hour or so for a minute or more depending, check e-mail, run a Time Machine backup, run daily clean-up scripts, download but not install updates, those sorts of things, then go back to sleep. Kind of like Sony and Microsoft's current gen game console will download and install updates while it's what most people will call "off." Apple, because they're Apple, they call this feature PowerNap, but intermittent wakes during sleep are a feature of lots of Windows laptops and desktops, too.
This is sort of interesting because pretty much the same thing happened with an old Creative X-Fi I have that I thought was just because the X-Fi was really old hardware. The X-Fi is purely bus-powered, no battery, but now maybe I don't think so. Same thing as the E17: wake from sleep, the MB Pro sees and keeps selected the X-Fi in the sound control panel, even the volume knob on the X-Fi will change the MB Pro's volume, but no ready lights, no audio out via any jack until I disconnected the X-Fi from USB and reconnected it. Which in a bus-power-only device with no battery, that's pretty much the same thing as a resetting the E17. The X-Fi resets because you completely power cycle it just disconnecting USB. The E17 has its own battery power so pulling the USB doesn't power cycle it, but the reset switch does.
I don't really have a solution yet, except probably just disconnect the E17 from USB when you're going to sleep your computer for a long time. It doesn't happen when I just put it to sleep for a short while. But I don't think it's the E17 and I don't think it's the dock. I think it's actually the computer and nothing wrong with that, either. Just the way it is.
But if you're E17 won't turn on and/or won't charge, make absolutely sure you are really resetting it properly because that might be the fix and you're not really hitting the reset button for long enough.