Adobe Premiere is driving me nuts

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Wanted to edit a project which had been edited before with an older Adobe CS version.
Turns out suddenly the import of the MP4 files is not anymore possible. Which is actually the right thing, because apparently the recoding was in incompatible formats, MP4 containers don't seem to support uncompressed audio. At least the video is fine.
But that was a whole damn week.
It took me 3 more days to decide for a lossy audio codec and find out what settings to use. Decided for AAC. Adobe Premiere crashes on that.
Seems it also doesn't like AC3 or MPEG2 audio, and also ffmpeg doesn't have stable converters for speex/opus/vorbis (and I cannot use mp3 because I have 4 audio channels). Now I'm at WMA2, which doesn't play on my linux machine, but it at least converts, und plays under Windows. Adobe Premiere still doesn't like it, now the playback is messed up, all goes to fast. Apparently something wrong with the audio settings (what?), guess that will take me a few more days.
The actual editing of the footage should take less than a day.
Efficient time use. At least I don't have much actual work at the moment.
What a waste.