[aml] grab as.xml from current profile rather than master

This should match the previous behavior
[aml] 1) fixed video buffer feed when showing still frames, 2) fixed typo (defaut != default) in ff/rw handling
[aml] add frame rate tracking
[aml] fixed some regressions, 100 bytes is too hi for still frames
[aml] fixed playback of video content with 24kHz audio