I'm assuming you have created a mod folder for this and not overwriting.
If you are keeping original sound names and only replacing the sound itself in my experience there is no need to reconcile in the sound volume editor or have an effect.xml in your mods sound folder. The reconciling may be the stumbling block in this case.
I have a personal sound mod of weapon, explosion, ambient, male voice and russian voice sounds where I have kept the original name and only replaced the sound. I have never reconciled it in Igor and it has never given me a problem.
It is not necessary to match the length of the original sound file either.
I don't think any of my altered files match the originals in length.
I replaced the distant combat.wav with a file that is over 2 minutes.
For my own use it is fine. I do worry about how that particular sound would affect lag on a server though.
Kafee's sound pack used only original sound file names and a effects.xml was not included in the mod.
Are you running your mod highest priority and is it only the one file giving trouble?
I'm confused about the term PCM. Is this the exact same thing as .wav format?
I tried nicking some sounds out of GRAW2 myself. IIRC they are stereo and when I converted them to mono they lost allot of quality so I gave up on using them.
For my own use I nicked allot of sounds from Chaney's Sound Mod for ArmA. They are 44100 Hz but they work fine in GR. Of all the sound packs I have d/l'ed it is far and away the best.
Last thought: take the effects.xml out of your mods sound folder and store it away.
Crank up GR and see if it plays.
Sorry about going on so long.