FWIW, I have the H10 set, with the "small tender" loco. It is all packed up and in storage at the moment while I sell my home of the past 15 years and relocate but prior to packing it up, I put quite a number of problem-free miles since it arrived around Christmas time.
The entire set was perfect out of the box and remained so until I packed it up a month or so ago. Great set and engine! No audio issues at all.