Emulator

When running target 60 FPS games in fullscreen mode inside Samsung DeX on an external display, after approximately 1 minute of gameplay, the frame rate consistently drops and fluctuates between 30 and 45 FPS, causing severe stuttering. Making or keeping the DeX taskbar visible on screen immediately restores performance to a smooth 60 FPS. Hiding the taskbar again causes performance to degrade back to 30-45 FPS after a short period.

Environment:

• Device: Samsung Galaxy S25+
• Docking Station: Official Samsung DeX Station
• OS / UI: Android 16 / One UI 8.5 (Samsung DeX)
• App Version: Dolphin Emulator (Tested across multiple versions)
• GPU / Driver: Adreno 830 (Turnip Drivers)
• Output: External Display / Big Screen via HDMI

Steps to Reproduce:

1. Connect the device to an external display using an official Samsung DeX Station.
2. Launch Dolphin and start any 60 FPS target game (e.g., Metroid Prime 3: Corruption).
3. Enter fullscreen mode on the big screen with the DeX taskbar auto-hidden.
4. Play for about 1 minute at 60 FPS.
5. Observe the performance drop (FPS fluctuates between 30 and 45 FPS).
6. Open/pin the DeX taskbar so it becomes visible on screen -> Observe FPS immediately restore to 60 FPS.
7. Hide the taskbar again -> Observe FPS drop back to 30-45 FPS after a short time.

Expected Behavior:
The emulator should maintain a continuous 60 FPS in fullscreen mode without the Android window manager throttling frame rates when the taskbar is hidden.

Additional Notes:

• Testing was performed using an official Samsung DeX Station to rule out third-party hub/HDMI power delivery or bandwidth issues.
• Keeping the DeX taskbar permanently visible/pinned on the external display prevents the issue entirely, as it forces the Android surface compositor to stay in windowed composition mode at 60 Hz rather than triggering the broken fullscreen state.
• With the taskbar visible, any game runs at 60 FPS in fullscreen mode.