Freeze on PS4 Pro

I am on PS4 pro with 4k/hdr television. The game every 15-30 seconds freeze the image for 1 to 4 seconds (even in the main menù/screen). I have tried to restart modem, i have tried even to use the DMZ mode on the modem but nothing. I have downloaded the game 3 times and even tried to rebuild database of the PS4. I have still this problem. What can i do? Thank you.

PS
I have even problem connecting with login (with the game not PSN), take a lot of times (1/9, 2/9, 3/9...Sometimes took 2 or 3 rounds to connect).