RTSP firmware will NOT flash

Got a couple new cams (V2s) - trying to flash the RTSP firmware but as per the instructions . Cams have 4.9.5.36 installed, setup and working .

  1. Hold the camera’s Setup button while plugging in the USB cable and continue to hold the Setup button until the light turns solid blue.

The light never turns blue, it will flash blur for about 1/2 a second but that’s it.
So whats the deal, any instructions that actually work.
Help!

It seems that the sdcard I was using was playing well with the cam. Got it to work.