hikvisionquest

Hello, all! We have a Hikvision DS-9616NI-I8 connected directly via HDMI to a 4k monitor, and a mouse and keyboard connected to the front USB ports on the NVR. Some time ago, the device is not allowing any kind of input, and we are not able to access the menu via either the mouse or keyboard. Instead, we see only the HikVision logo in a 4x4 grid (see image). Pushing the buttons on the front panel also does nothing. Even holding the power button for 3+ seconds will cause a beep, but will not power the unit off. I can access the NVR via web browser, and according to the lights on the front panel, it is recording just fine. I just am not able to access the menus. For troubleshooting steps, i've tried: Move mouse/keyboard to different USB ports Change output resolution for HDMI between 1080p and 4k Access NVR via SADP tool to verify password is still correct Access NVR via IP address in web browser to verify connectivity and cameras are working Verify front-panel lights according to user manual Reboot via web interface (boot up screen shows - see image) Upgrade firmware from 4.1.11 to 4.5.00 Try all buttons on front-panel and USB keyboard to prompt some action After all troubleshooting, still I only see this screen. I can tell the keyboard/mouse activity is detected, because the screen will briefly flash black after multiple clicks/key presses. Hoping the smart folks here can help me out. Have a good day!