You have a configuration issue (#3) so I didn't bother to go through the entire log, I actually stopped right here:
10:26:32.568: audio settings reset:
10:26:32.568: samples per sec: 48000
10:26:32.568: speakers: 2
10:26:32.568: max buffering: 21 milliseconds
10:26:32.568: buffering type: fixed
10:26:32.570: ---------------------------------
10:26:32.570: Initializing D3D11...
10:26:32.570: Available Video Adapters:
10:26:32.571: Adapter 0: AMD Radeon RX 7900 XTX
10:26:32.571: Dedicated VRAM: 25707913216 (23.9 GiB)
10:26:32.571: Shared VRAM: 16704772096 (15.6 GiB)
10:26:32.571: PCI ID: 1002:744c
10:26:32.571: HAGS Status: Disabled (Default: No, Driver status: Unsupported)
10:26:32.572: Driver Version: 32.0.31041.1004
10:26:32.573: output 0:
10:26:32.573: name=VG27AQ1A
10:26:32.573: pos={0, 0}
10:26:32.573: size={2560, 1440}
10:26:32.573: attached=true
10:26:32.573: refresh=120
10:26:32.573: bits_per_color=10
10:26:32.573: space=RGB_FULL_G22_NONE_P709
10:26:32.573: primaries=[r=(0.677734, 0.309570), g=(0.265625, 0.663086), b=(0.148438, 0.052734), wp=(0.313477, 0.329102)]
10:26:32.573: relative_gamut_area=[709=1.307270, P3=0.963682, 2020=0.691377]
10:26:32.573: sdr_white_nits=80
10:26:32.573: nit_range=[min=0.000000, max=603.698425, max_full_frame=603.698425]
10:26:32.573: dpi=96 (100%)
10:26:32.573: id=\\?\DISPLAY#AUS2707#7&131a9964&0&UID512#{e6f07b5f-ee97-4a90-b076-33f57bf4eaa7}
10:26:32.573: alt_id=\\.\DISPLAY2
10:26:32.574: output 1:
10:26:32.574: name=ASUS VE278
10:26:32.574: pos={-1920, 350}
10:26:32.574: size={1920, 1080}
10:26:32.574: attached=true
10:26:32.574: refresh=60
10:26:32.574: bits_per_color=8
10:26:32.574: space=RGB_FULL_G22_NONE_P709
10:26:32.574: primaries=[r=(0.647461, 0.333984), g=(0.284180, 0.607422), b=(0.151367, 0.071289), wp=(0.313477, 0.329102)]
10:26:32.574: relative_gamut_area=[709=1.031160, P3=0.760141, 2020=0.545350]
10:26:32.574: sdr_white_nits=80
10:26:32.574: nit_range=[min=0.500000, max=270.000000, max_full_frame=270.000000]
10:26:32.574: dpi=96 (100%)
10:26:32.574: id=\\?\DISPLAY#ACI27F6#7&131a9964&0&UID524#{e6f07b5f-ee97-4a90-b076-33f57bf4eaa7}
10:26:32.574: alt_id=\\.\DISPLAY3
10:26:32.574: Adapter 1: AMD Radeon(TM) Graphics
10:26:32.574: Dedicated VRAM: 509353984 (0.5 GiB)
10:26:32.574: Shared VRAM: 16704772096 (15.6 GiB)
10:26:32.574: PCI ID: 1002:164e
10:26:32.574: HAGS Status: Disabled (Default: No, Driver status: Unsupported)
10:26:32.575: Driver Version: 32.0.21045.5002
10:26:32.576: output 0:
10:26:32.576: name=S27D390
10:26:32.576: pos={2560, 350}
10:26:32.576: size={1920, 1080}
10:26:32.576: attached=true
10:26:32.576: refresh=60
10:26:32.576: bits_per_color=8
10:26:32.576: space=RGB_FULL_G22_NONE_P709
10:26:32.576: primaries=[r=(0.639648, 0.330078), g=(0.299805, 0.599609), b=(0.149414, 0.059570), wp=(0.312500, 0.329102)]
10:26:32.576: relative_gamut_area=[709=0.999839, P3=0.737052, 2020=0.528786]
10:26:32.576: sdr_white_nits=80
10:26:32.576: nit_range=[min=0.500000, max=270.000000, max_full_frame=270.000000]
10:26:32.576: dpi=96 (100%)
10:26:32.576: id=\\?\DISPLAY#ACI24C5#7&131a9964&0&UID516#{e6f07b5f-ee97-4a90-b076-33f57bf4eaa7}
10:26:32.576: alt_id=\\.\DISPLAY6
10:26:32.576: Loading up D3D11 on adapter AMD Radeon RX 7900 XTX (0)
10:26:32.591: Enabling fixed audio buffering, total audio buffering is now 21 milliseconds
1. Disable low latency mode.
2. Your main monitor is running 10-bit color, it should be 8-bit like the rest of your monitors. Most likely the Color Bit Depth Setting in the AMD Control Panel.
https://www.amd.com/en/resources/support-articles/faqs/DH3-008.html
3. Connect your S27D390 to your GPU, it's currently connected to your mobo (iGPU)
Test & see if there's any improvement.