I to have the exact same issue with the PS4 Pro connected to the VR breakout box. TV is a SONY 2014 4K (non HDR), all HDMI are 2.0 and HDCP 2.2. I had an issue after booting the Pro where the I would get no steady video signal until at least 1m10sec. Before this i would get flashes of sound, then flashes of video, then both would come through on the TV. After say 5 mins post boot, I would loose both video/sound for 2-5secs then signal returned, sometimes the would not??
Non of the above issue are there if I connect the Pro directly to the TV, but this isn't really an option due to the way my equipment is set up.
I have now managed to get the signal to come through after about 10-15secs, when connected to the VR breakout box by going into the main console settings and turning off HDCP setting. I still get the loss of signal after 5 mins though?? I have also figured out that if the video signal returns but the audio doesn't, all I have to do is press the PS button on the controller, go to screen/sound settings and change the audio chose to PCM then back to Dolby Digital which I have the console set to and the sound returns. Still a pain but at least I don't have to restart the whole console.
I have contacted Sony support at least 4 times now and each time they have told me I was the firs person to have contacted them with regards to the matter??? The last person I spoke to told me the VR breakout box didn't support 4K and I had to connect direct to the TV, when I told him I was getting 4K on the TV through the breakout box, he put the phone down on me, lol.
This needs sorting out ASAP as I haven't spent the best part of £1000 on 2 Playstation product, which were released 1 month apart, for them not to work properly together. I understand these are new products but Sony haven't even made any statements regarding the issue or lettings us know there is a fix in the works.
How they have released the VR box knowing the Pro was being released the month later and not have the box fully support all features such a HDR, which the VR box will not pass is mind blowing.
I am so glad that this has finally been reported on, now Sony may have to make a statement. I even contacted Digital Foundry to see if they would have a look into what may be happening but never heard anything back from them. I can also comfirm i had non of these issues using the launch day PS4. but I got rid of that before both 4.06 and 4.07 firmwares were released so maybe it has something to do with either of those firmwares.