Problem 1) Internal / External mic switching.
With firmware version 1.04 and my third Sony A77!! I had it stuck on internal mic only. The cure from Sony support is to reset the camera (menu, movie & play buttons) while having the external mic plugged in. This worked and even became premanent after the second time. The camera now switches between internal and external mics. I think it only swiches at the start of recording and if the external mic is pulled out I think it stays on external until you start recording again.
Problem 2) Hot or bright pixels in low light areas in movie mode
This seemed to appear after the above but earlier videos may have the 'red spot' I had, it just did not show in these brighter scenes. The cure is to fool the camera into resetting it's black level pixels cancellation - or another set of words along those lines - If you up the date by one year (that seems the easiest way to alter it) and do a reset and initialize, this cures the problem. Without changing the date the camera does not do the update or cancellation. Sony support did not offer this. It came from photobuf on YouTube.
Hope this helps someone.
