This is what I just now sent to DJI support:
Today, June 24th, I boot up my P3P and there is no video signal with the error: "No Image Transmission Signal" and the video signal would turn on then turn off and was very choppy looking with lots of video artifacts in the signal.
When I searched the DJI Phantom 3 forums for "No Image Transmission Signal", it appears a lot of people are having this same problem after they had updated to the new firmware release P3X_FW_V01.09.0060
But they also found a solution to the problem: they took the MicroSD memory card out of the Phantom's camera drive and the video image transmission became stable.
I have several MicroSD cards:
Lexar 633x 16GB UHS speed class 1 in a "U" and class 10 in a "circle" - 10MB/s transfer speed (this is the MicroSD card that came with my P3P)
SanDisk Ultra Plus 16GB UHS speed class 1 in a "U" - 10MB/s transfer speed (this MicroSD card was designed specifically for 1080p video)
SanDisk Extreme Pro 32GB UHS class 3 in a "U" - 30MB/s transfer speed (this MicroSD card was designed specifically for 4K video)
Before I installed the P3X_FW_V01.09.0060 firmware update, my SanDisk Extreme Pro 32GB UHS class 3 in a "U" MicroSD card worked fine and the video transmission signal was perfect.
AFTER I installed the P3X_FW_V01.09.0060, all I get is "No Image Transmission Signal" error.
But when I use the SanDisk Ultra Plus 16GB UHS speed class 1 in a "U" MicroSD card in the P3P, for now, I get no video transmission signal errors.
Flying my P3P without a memory card is not an option.
DJI, you need to fix your update so that we can use memory cards up to the promised 64GB and be able to use MicroSD cards designed to record 4K video.
So yes, if I remove the MicroSD card, the video signal missing problem goes away.
If I use the substandard SanDisk Ultra Plus 16GB UHS speed class 1 in a "U" I get a stable video signal but this card was not designed to record 4K video smoothly.
This problem needs to be fixed ASAP.
By the way, this link was helpful in my writing this to DJI:
Secure Digital - Wikipedia, the free encyclopedia