Traction motors going silent after 45 MPH

I am trying to add traction motor effects labeled as a track sound to a locomotive from the DLS. "Locomotive Traction Motor Sound kuid2:45324:53000:1". It seems that when the locomotive surpasses 45 MPH, the track sound effect goes silent. Is there a way to fix this?

Load another sound file to commence at 45mph?

Other tracksounds I have set with other trucks work fine at speeds above 45 MPH. It seems it is just that one I want to act as a traction motor does not. What can be done to fix this issue?