Input prepare and dynamic inputs
You can prepare for an input switch when the associated input is a dynamic input. A dynamic input has a variable in its path. Each time that you add the input to the schedule, you specify a replacement string to replace the variable with a file.
When you set up the prepare input action, you must specify this replacement string. The string must exactly match the replacement string in the switch action. If the strings are not identical, MediaLive won't prepare the input in advance.
You might use this dynamic input more than once in the channel, and the replacement string might be different in each instance. Make sure that you change the string in each prepare action.