Hi, I'm wondering if I'm running Channels DVR on a Synology NAS, can I plug a USB hard drive into the unit and save recordings there? Is this possible?
I'd rather keep my WD Reds for critical data (photos/videos) and keep my recordings on a separate drive.
Yes, it's possible.
Sorry to jump on an old thread but it’s relevant - will time shifting record to the USB as well as recordings?
No. Time shifting the live buffer happens on the client device, not the server.
Thanks, of course it does, was a daft question if I’d stopped to think about it 
What would the time/shift folder be on a Shield, internal memory plus any adopted storage?
It depends upon where the Channels app is installed. If the app is installed on the internal memory, that is used for your buffer; if you installed/moved the Channels app to your adopted storage partition, then that is where the buffer will be located.
Great, thanks. Sorry one more question 
What’s the best type of adopted storage to use, I’ve destroyed two USB sticks and an SD card so far due to the constant writing.
Personally, none. But if you're dead-set on on using external storage, use a USB hard drive that has an external power supply. Most every Android device cannot supply enough power to the USB ports to get consistent IO.