Ran the SD40 on SPG for the first time this evening and have to say the horn sounds amazing?? BUT and it's a big but about 3/4 of the way in the horn got stuck on and I tried the old move the external camera far enough away from the train and it did switch it off but then for the rest of the run from the cab I could hear the horn starting far away but getting closer as I proceeded down the line, once passed the peak it would slowly quieten as if the horn was stationary at a point on the track and I was passing it. Once it had stopped it would repeat at a future point on the track. I'm in the process of uploading the whole run onto YouTube if anyone from DTG cares to watch it back. Weird is not the word!!
I recall having that issue _ages_ ago on SPG, I don't think it's new (just maybe a little less common than the stuck horn).