(I posted this on Sero7Forum a few weeks ago. I thought it might be helpful here)
Woke up this morning and my Chromecast was dead. The indicator light was red but on. The TV was getting a signal but it was just a black screen. Did a little research. Google recommends resetting it and I guess there is a known issue with the reset button sticking. Well, that didn't help. Then someone at android central recommended replacing the USB cable. I tried that and it fired right up.
It is amazing how many issues I've seen solved by swapping out the cable. Charging, syncing, flashing Roms. It is an easy first step in resolving many issues.
You might think your usb cable is fine. It seems to work. Problems with a usb cable can be intermittent.
Sent from my Sero 7 Pro using Tapatalk.