I'm having a problem with the internal speaker (not system beep!) of my Optiplex 380 Mini Towers.

The machines came without internal speaker, so I connected the ones from my old Optiplex 360 machines (same connector, same method of clipping them on the chassis). But they only give me a "clicking" sound followed by the actual sound in a almost not audible volume, even if volume is on max.

The speakers themselves are ok, tested them in 360 machines and they are working fine.

Any idea that could help me? Thanks!