Stereo-to-mono glitch when match-framing

While searching for an answer I found a posting from ChiaMac dated Nov. 15, 2005 which describes the same problem I am experiencing. I have pasted the post below. Does anyone have an answer ?
Hi,
Three different editing systems, all running OS 10.3.9 and FCP 4.5 -- an iBook G4, PowerMac G5, and PowerMac G4.
Quite often, when match-framing in the timeline to bring up a clip in the viewer, the viewer will show dual mono audio, whereas the source clip has stereo audio. Then, when I try to cut that viewer clip into the timeline, in this sequence or another, it will be dual mono. Quite irritating.
It is quite replicable. Not all clips will produce the stereo-mono result, but it is replicable with the same clips over and over.
The "linked selection" has no effect on the process, no one has pressed command-L by mistake, and all audio settings on each of the systems are set to capture and output in stereo.
Is this a known FCP 4.5 HD glitch? I haven't seen it listed anywhere when I've searched for it. Any ideas, suggestions...?

>When converting a file from stereo to mono, Audition severely suppresses the amplitude of the entire file. This happens when using both the Convert Sample Rate method, as well as exporting a file from multi-track.
>It gets weirder: files that were recorded quite a while back will process this conversion just fine, but newer ones will not. All files are recorded in 16-bit 44100 stereo and saved as a Windows PCM wav file - so as far as I can tell there is no difference and I'm simply confounded.
Generally when this happens, it means that there isn't that much stereo (ie, difference between the two channels) in the file anyway, and one of these two channels is inverted - so that what happens when you combine them is that the 'mono' parts then cancel out, rather than add together, and all that's left is the difference - which looks pretty much like what you've got.
To test this, the thing to do is to select one channel only in EV, and invert its polarity (Effects>Invert). If you now get more like the waveform you were expecting when you convert to mono, then you've found the cause. But not necessarily the reason for it...

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Jerry
Message was edited by: Jerry Hofmann

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Once again I'm starting a new thread to explain some general audio principles that newbies have trouble with.
There's an issue here that's a bit difficult to explain--the difference between "stereo" and "mono".
You have two ears, so you hear "stereo". Your ears send a left signal and right signal to your brain. Your brain processes the difference between the two signals and gives you a sense of direction. You can figure out where the sound you are hearing is coming from.
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Hi,
I want to use case statement in the when matched clause of merge statement to ensure that I update only those fields that are undated.
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Stereo-to-mono glitch when match-framing

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