ubuntu 20.04 / nvidia 440.59 VT1-VT6 switch from X (VT7 2560x1440 120 Hz) - no signal

Before I noticed this problem from time to time: VT switch to text console not works - I get no signal on monitor(DisplayPort/DFP5) if I try switching from my X screen (VT7) to any of linux text console on VT1-VT6 by ctrl-alt-F* keys. Going back by alt-f7 works. On 440.59 is reproduced always, on previous versions worked sometimes - like on login screen(60 Hz) not worked, after login to X(120 Hz) - worked. Currently I use nvidia-drm with modeset = 1, my boot is EFI, grub works in efi mode. Is modeset with nvidia driver still not stable - should I turn it off? Or maybe there is some problem with 120 Hz mode?

X.org server is: 1.20.7
GPU is: NVIDIA GPU GeForce GTX 1080 Ti (GP102-A)
Monitor: ASUS ROG Swift PG279
X screen desktop mode: 2560x1440 @ 120 Hz (g-sync disabled)
Linux kernel: 5.4.0-14