An update on the problem I was having with interference/noise when listening to files from the SD card (with my JH16s) -
I purchased the GAME amp and installed it, and - no more noise. Finally!
(Now I'm going to ask for either a refund for the GAME amp, or a replacement amp module that works with my JH16s - still not clear what the problem was - I still haven't seen a lot of talk about this being a widespread issue, so maybe it was just a bad amp (or a bad batch of amps).
Hope this helps
Your issue is the the original batch of standard amp modules gain settings were set to a bit higher than suitable for ultra-sensitive IEMs such as the JH16 Pros. This has now been rectified in newer batches, so the standard amp modules now will work without any hiss/IF with these IEMs as well as most full-sized cans.