IIRC you need something at the end of the chain after the TBD for MDP to work (eg an HDD or something). I read that years ago though, would like to know if that's still the case.
OP, you could look at a USB 3->HDMI adapter. The USB 2 ones were pretty slow but from what I've read the USB 3 ones run very well and I imagine it would be absolutely fine for 24 FPS. I don't know if they support audio though.
You can absolutely run two external monitors off a MacBook Air 13", but you need two *thunderbolt devices* in the chain. I have successfully done the following for most of the past year:
- MBA 13" (2015)
- Thunderbolt 2 elgato dock with 2x Thunderbolt ports & HDMI -> Monitor 1
- Thunderbolt 2 HDD with 2x Thunderbolt
- mDP adapter -> Monitor 2
In your case, the Thunderbolt monitor takes the place of the TB2 Dock with HDMI out. You will not be able to take a mDP adapter and stick it into the downstream TB port on the monitor. However, if you have another TB device with passthrough, you CAN stick it into the downstream port on that device if it follows the monitor.
Apparently, the TB data stream has 2 DP streams encapsulated in it, but each TB device is only capable of decoding 1 of them by default. So you have the monitor decoding one, I have a dock decoding one. The second one is unavailable unless there is another TB device in the chain.
Targus does make a TB2 dock which has two DP out -- it apparently decodes both TB video streams internally.
That's been my experience, at least. YMMV.
Hope this helps!
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