Apple is gradually building a more inclusive ecosystem. Take the MacBook Pro M1 Pro as an example -- it made headlines for its highly anticipated Dual Display feature. While the base M1 model only supports one external monitor, you can use up to two third-party output devices on M1 Pro and M1 Max.
The thing about new features, however, is that they're not without kinks. Dual Display has recently been acting up on macOS 15.1 and 15.2. And troubleshooting is such a hassle because you'll have to check your MacBook, external monitor, and macOS. To speed up things, start with the most likely causes. Here's what to do.
Try connecting your monitor to a different port on your Mac. Ports on opposite sides often use separate internal controllers, so switching can resolve minor connectivity issues. And if the port looks dirty, gently blow into it to clear out loose debris.
You have to consider that your Mac might not be the problem. Hardware issues, unsupported resolutions, or firmware problems on your external display can also cause connection failures. Try using another output device to trace the issue. You can set your iPad for Dual Display if you don't have access to another computer monitor.
If both external monitors work, try checking your cables. Damaged cables, or those that don't support high resolutions and refresh rates, can mess with your display. Even if your cable looks fine, wear and tear can cause invisible issues like incomplete data transfers.
Your Mac might be set to a resolution or refresh rate that your monitor doesn't support. Try adjusting these settings manually.
If you can't fix your display settings manually, reset them altogether. It's a quick way to clear misconfigurations, although you'll also have to set your previous preferences from scratch.
The problem might not be your fault at all -- it could be a macOS bug. Dual Display issues are actually quite common on macOS 15.1 and 15.2, try updating to a more recent stable release. Apple is pretty quick to resolve known bugs.
If nothing else works, a factory reset might be your best bet. It'll wipe your system and restore macOS Sequoia to its original state, clearing software issues or misconfigurations. Just remember to back up your device beforehand.
Contact Apple Support for help with your MacBook if these solutions don't work. For external monitor problems, reach out to the manufacturer directly. Of course, you could also continue troubleshooting by reconnecting your Mac displays. Your persistence might pay off after a few more force restarts.