I have a Digitrax sound module i have attempted to install in this engine, but keep  having problems.  The functions work porperly, but the sound is extrememly weak.  I have attempted to do research on baffling and have made one that allows me to install the speaker in the upper compartment of the tender, after having drilled many small holes to accomodate the sound output.  Anyone have any suggestions on increasing sound level.  Checked with Digitrax and they are saying I am installing it properly. . . Any help would be appreciated.