A repetitive clicking noise coming from a laptop is usually a sign of a failing hard disk drive (HDD), which is a type of storage device that uses spinning platters and moving heads to read and write data. A failing HDD can also cause severe delays in input and output operations, as well as data loss or corruption. The technician should replace the HDD with a new one or upgrade it to a solid state drive (SSD), which is another type of storage device that uses flash memory and has no moving parts. Reference: https://partners.comptia.org/docs
/default-source/resources/a-core-series-combined-content-guide (page 24)

The message to clean the air filters, despite them being clean, is likely due to the projector's preconfigured settings related to the hours of use. Many projectors have maintenance reminders that trigger based on usage hours to prompt regular cleaning and maintenance. This reminder may need to be reset after checking or cleaning the filters. Adjusting the maintenance reminder or resetting the hours of use counter in the projector's settings can resolve the issue. This approach is consistent with the troubleshooting principles outlined in the CompTIA A+ Core 1 (220-1101) Exam Objectives under section 5.4 "Given a scenario troubleshoot video, projector, and display issues", where it's advised to consider all potential causes, including preconfigured settings, when diagnosing display-related problems .

The technician should ensure the input connections to the screen are secure1. The screen may not be receiving the signal from the device outputting the data if the input connections are not secure1. Swapping cables with a screen that works is not likely to be the correct option1