Preface: I know this is a niche issue, but...
I recently upgraded my rig to Ryzen R7 1700 using the Asus B350 Prime Plus mainboard. I picked this mainboard because it has 2 regular PCI slots on it, which I use for my Auzentech X-Meridian 7.1 PCI Soundcard with X-Tension card. This soundcard has hardware MIDI support, which I use with a Roland SoundCanvas synth. I am running all of this under Windows 10 Pro x64.
Initially tested under Windows 10 1607 (Anniversary), also tried with 1703 (Creator's). Windows 10 has been fresh installed on a clean drive for each test.
System crashes within 1 minute when playing MIDI files through the hardware MIDI port. This happens with Winamp (which natively allows MIDI out selection), Media Player Classic and Windows Media Player (when using Coolsoft MIDIMapper to change default MIDI output to hardware MIDI port). This happens regardless if using the DirectMusic API or outputting directly to the port. It happens regardless of MIDI file played. This crash does NOT occur when using Window's built-in software synth.
I did not have this crash using the otherwise same hardware and software on my old AMD FX 8320 CPU and Asus Mainboard. My wife's older hardware was replaced with my FX 8320 setup. Moving the hardware back to her PC results in no problems, which means the issue is specific to my new hardware (Ryzen CPU, Asus B350 Prime Plus Mainboard, Corsair RAM - all other hardware and software is the same between the 2 systems).
Tried Asus B350 Prime Plus BIOS revisions 0503 and 0605 Beta (with AGESA 1004A) to resolve the issue - with BIOS 0503 the crash is a hard lock (I have to unplug the PC power cord to recover). with 0605 it just seems to reboot itself.