Thank you very much for your help.

I am such a novice, like who would be able to do that?

the spectrum engine has an on board decoder but i have no way to access it. i am using the engine with a DC controller and the factory presets are too loud. what other equipment do i need in order to reprogram the decoder?

yes, but how do we access the decoder to reset the value on cv 128. we are using the engine with a regular dc controller

We have recently purchased a Spectrum DCC locomotive but the sound is to loud - is there any way to adjust the volume?