Callouts and some other sounds are the function of a guage in some cases, not a sound file. Is there a "sound" folder in the subject 737 folder?

Does your aircraft.cfg file have a line entry for each 737 variation such as:
[FLTSIM.0]
model=
sim=xxxx
sound=


[FLTSIM.1]
model=
sim=xxxx
sound=
etc?????

Does the SOUND folder contain a sound.cfg file that is an alias to another aircraft? If so, is that alias'd aircraft exisiting in your aircraft directory? If not, no sound files will be activated

If there IS a Sound folder in your 737 directory, does it have a suffix in its name, like sound.A,  sound.B,  Sound.737, etc?

If so, the reference in the aircraft.cfg file must be altered to show the suffix; in other words, sound=A, sound=B, sound=737, etc

I hope this might give you some help. It is strange that if you used an auto-install feature that you would have such a problem

Regards
Mike