these are all the same issue and i have the solution for it.
Adobe has once again let down the non professional user buy ignoring this bug. They have also deleted alot of my other posts on the adobe forums.. perhaps so you cannot receive help from me?? who freakin knows..
you import your footage and there is no audio in the time line. you see the audio clip there but no information in it. some people say its because of MPEG format but MPEG files works fine in Windows Movie Maker, Ulead, Pinnacle, Sony Vegas.. etc...
let it be known that its an Adobe Premiere issue.
close adobe premiere
open My Computer and go to tools at the top. From the drop down menu go to folder options. In folder options click the view tab. In the advanced settings section where it says 'Hidden files and folders' make sure 'show hidden files and folders' is selected.
open My computer and go to c:\ drive > Documents and settings. Now click into your user name (NOT 'All users') in my case its 'proGamer'. Now click into 'Application Data' > 'Adobe' > 'common' > 'Media Cache Files'.
in this folder find the files you were just trying to import by searching the name. in my case its file: 20081217030338. you will now see 3 different file types with the same file name you were importing: CFA, PEK, MPGINDEX. delete them all!
go back and open adobe premiere, open up your project again and it will automatically recreate those files you just deleted. hopefully correctly.
If this hasn't worked then open your adobe premiere project, clear all trace of the files with no audio and start again from step 1. then after step 5 just import the files back into your project.
This has proved to work with every file i've imported that had the audio not conformed.
your second option:
simply play your clip in WMV or VLC or what ever player you use and record the audio in real time in stereo by using some music editing like cubase or logic audio. you can also use something more friendly like 'recordpad' found here: RecordPad Professional Sound Recording Software - Screenshots now you can buy it from these guys or get it how ever else you like
If you like you can visit my youtube page with any other questions about this issue or other things i may be able to assist with. melbourneJester is the username. only 5 simple clips up there at the moment as its a new account i'm still editing so many comedy scetches so i can post up there so please be patient and subscribe to be alerted of the vids when they're posted.
good luck guys and create some good shit =)