I received my Smabat ST-10 replacement few days ago. Jim at NiceHCK provided an excellent support and took care of all the expenses.
Everything works very well now. They fixed the problem with the cable and the MMCX connectors. I moved the connector around a lot while listening to check if I could recreate the problem and I was never able to do it.
I continually used the ST-10 in the past days, only switching them, here and there, with the NiceHCK EBX for comparison.
The EBX sound is very similar to the ST-10, the EBX has a little more balanced sound across the frequency spectrum but the ST-10 has better lower bass.
I mostly listen to Jazz and Progressive Rock and the ST-10 proved to be a great all rounder with these two genres.
I would like to thank ClieOS for recommending it and Jim at NiceHCK for the outstanding support.
Does your second pair sounds the exact same as your first batch? (just for stats purpose)
My second seems to have very slight more forwarded mids (which is not bad depending on tracks, but I still prefer my first batch for electronic musics)