Diagnosis
Interference on the 2.4GHz Wi-Fi band or a power-saving setting disrupting the connection. The projector's Wi-Fi module is sensitive to signal congestion.
How to Fix It
Connect to a 5GHz Wi-Fi network if your router supports it. The 5GHz band is less congested. In projector settings, go to Network & Internet > Wi-Fi, select your network, and ensure it's the 5GHz SSID. If only 2.4GHz is available, move the router closer.
If That Didn't Work
Disable the Wi-Fi power-saving feature. Go to Settings > Device Preferences > Power > Wi-Fi Power Saving Mode and set it to OFF. This prevents the system from suspending the network during playback.
Heads Up
The metal body can attenuate signal. Avoid placing the projector with its Wi-Fi antenna area (near the rear ports) directly against a wall or large metal object.