Card quality varies enormously, and not only between brands. Two cards from the same vendor can behave very differently, so the card is worth choosing deliberately rather than using whatever came with the board.
What to buy
Use a Class 10 card. Anything slower will hurt playback.
Use 16 GB or larger.
We ship SanDisk Industrial grade cards in our pre-built players, part number SDSDQAF3-016G. If you want to match what we run, that is the card.
Why grade matters more than capacity
A signage player writes to its card continuously, for years, with no one watching. That is the workload consumer cards handle worst, and a card that is fine in a camera can fail in a screen within months.
A failed card is a site visit. On a screen that is awkward to reach, the difference in price between a consumer card and an industrial one is recovered the first time you do not have to drive to it.
If a card fails
Write a fresh image to a new card and pair the device again. Nothing is stored only on the device, so a screen rebuilt from a new card comes back with the same content and schedule.
Write the image has the steps.