While students are working on their create apps in app lab, many of them are exploring some features that are not explicitly included in the lessons for CS Principles.
One example, a student is creating an app that concludes with a song being played. She uploaded MP3 files and her code works, but she experiences >20 second lag time between her event and the playback beginning. Lag time increases if she runs her app using a device with a slower processor, but when she uses her personal macbook pro (fastest processor we have tested with), she still gets >10 seconds lag time between the time a song should begin and the time the audio comes through the speakers. My class PC’s have slower processors and have even more lag time. I remember that last year a student had lag time between events and MP3 playback as well, but with much shorter lag times (despite having faster computers in my classroom this year).
In all cases, students are uploading their MP3’s to App Lab and using playSound() to initiate playback. Any help or guidance to reduce lag time is appreciated.