I just tried this, and the results seem good. Both levels were recorded 1m away from the phone in a room with 27db ambient noise, with the same song playing each time.
Before mod - 67db average - Couldn't really hear my ringtone in a moderately busy room.
After mod - 80db average - Can just about hear my ringtone in the same room.
One thing to note was that I only put one hole on the front and one on the back of the module, I won't be adding more as im very happy with the volume at present. Cheers for trying this out and sharing this Adam
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