Display shifted to right in certain video modes

[G30FF]

I'm running RetroPie 4.7.2, on a Pi 4, with all the latest OS updates installed. When hooked up to my Dynex TV, it natively wants to display in a very weird, non-standard resolution. I'd like to force the Pi into 720p or 1080p mode. In raspi-config, I set the display mode to 4 to force 720p mode. After rebooting, the screen shifts off to the right by a noticeable margin, cutting off the right side of the screen. If I set the display mode to 16 to force 1080p mode, this shift is even larger, and the left margin is so large that 1/3 of the right side of the screen is hidden.

I tried to set negative overscan values on the left side in /boot/config.txt to force it back into place, but negative overscan values have no effect on the left side. Top, bottom, and right overscan values work, and positive overscan values on the left do shift the screen more to the right, but they do nothing to get the screen to move back to the left. If anyone has any insight, I would be very grateful.

[mitu]

Do you have overscan_scale=1 in /boot/config.txt ?

[G30FF]

@mitu It was commented out in my /boot/config.txt file. I uncommented it, but it had no effect. Here is my current config.txt file:

# For more options and information see
# http://rpf.io/configtxt
# Some settings may impact device functionality. See link above for details

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
hdmi_mode=4

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv_mode=2

#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

# Uncomment some or all of these to enable the optional hardware interfaces
#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on

# Uncomment this to enable infrared communication.
#dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18

# Additional overlays and parameters are documented /boot/overlays/README

# Enable audio (loads snd_bcm2835)
dtparam=audio=on

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
dtoverlay=vc4-fkms-v3d
max_framebuffers=2

[all]
#dtoverlay=vc4-fkms-v3d
overscan_scale=1

disable_splash=1
#enable_tvout=1

I should add that after uncommenting overscan_scale=1, I also tried uncommenting overscan_left and setting it to -16. It also had no effect.