No working H.264 + Audio Format combination

[Olio]

Hi,

I'm currently working with raw Fraps footage and want to convert in a pretty high quality H.264 to minimize the filesize (for temporary storage, after that I need to edit it in an editing program)
I'm using the Very Slow preset with 18 MB/s and encoding video only works fine. But if i enable audio and set a proper format (like LC-AAC) the progress always stops at the same percentage with the error

"The decode thread seems to be blocked. If you are not running other program..."

I already tried setting different CPU affinitys/priorities and other audio formats but its always the same.
Using MP4 Container btw.

Maybe someone has a working preset I could try out or something to help me out here

[05-06 22:55:12] Attempting to start built-in HTTPd on port 19819 [HTTPd]
[05-06 22:55:12] Built-in HTTPd started on port 19820 [HTTPd]
[05-06 22:55:12] Initialized
[05-06 22:55:20] Scanning plugins
[05-06 22:55:44] Start transcoding job for S:\Fraps\BFBC2Game 2010-04-26 18-06-33-92.avi
[05-06 22:55:45] x264 loaded
[05-06 22:55:45] Starting encoder (x264)
[05-06 22:55:45] Starting encoder (FAAC)
[05-06 22:59:04] Audio buffer underflow, decoding thread blocked, encoding thread to exit. [AudioEncodeThread]
[05-06 22:59:04] Waiting for process to terminate
[05-06 23:01:06] Audio buffer overflow, encoding thread blocked. decoding thread to exit. [AudioDecodeThread]
[05-06 23:03:29] Video buffer underflow, decoding thread blocked, encoding thread to exit. [VideoEncodeThread]
[05-06 23:03:39] x264 unloaded
[05-06 23:03:39] Error occurred during video transcoding.
[05-06 23:03:39] Finished transcoding job for S:\Fraps\BFBC2Game 2010-04-26 18-06-33-92.avi