Just received my Note 5 ordered from GEMFIVE through SURE REACH courier service and not SenQ.
On checking with GEMFIVE, they told me the reseller is QFSYNERGY and the warranty is only 1 year from Samsung.
Has anyone had similar experience?
I thought all orders go through SenQ which offer extra year of warranty.

It could be caused by certain music file. Was it always stop at the same song or was it stop randomly? Also, what music you are using? I have used quite a number of music apps since I joined android family and I found out some music apps do have this kind of sudden pause problem.

Video also the same? The first thing i could think of is the head phone jack problem. But since you said your Bt earphone is also having the same symptom, then only one possibility left which is the issue is coming from the phone system itself. Not sure if the phone system corrupted or you have changed something in the phone setting which some how affected the playback. It's hard to pin point the real cause.

If nothing helps, perhaps you should reset the phone and see if this solve the problem.