USB Audio Interface Mystery

Question

I have an HP Envy TouchSmart m7.  Purchased it with Win 8 and upgraded to Win 8.1 update 1 (with August 2014 update).
No issues with the exception of a USB device.  I normally have not used any USB devices - no USB keyboard, no USB printer, etc.. I have used a USB mouse once in a blue moon - but I do use a USB audio interface for my MIDI keyboard regularly.
It works fine until I connect a cable from any of the outputs to a mixer or amp.  Within minutes, I hear a click and my audio driver stops responding as if the device rebooted - I'm assuming because of a USB power or data drop-out.  I've replaced my audio interface, tried different power sources, different locations, all types of surge strips, modified power settings, replaced mixers, upgraded my BIOS, checked Windows updates, been talking with the maker of my audio interface (who even sent me custom drivers) and talking with the makers of my music software - all of them are at wits end saying to simply use another computer.
Help - help and help!  I cannot perform with my audio interface not working.  I have to connect it in order to hear sound.  Everything seems to point to hardware on my laptop.  Any ideas or fixes for this laptop?
Thanks,
Chris

Answer 1

Hello,
AS I stated earlier - the maker of the problematic device (which has a solid reputation) has sent me new drivers that aren't widely available although the drivers seemed and still seem solid and I've never mentioned nor had an issue with latency.  Although you said I didn't mention updating any of the drivers, I may have inferred it by saying I installed any and all Windows updates which included drivers.
I have worked with PC's for 20 years, building, supporting, programming, etc.. I have seen a plethora of problems that run the gamut of easy to very complex and even to unexplainable - which I usually don't accept.. lol.  This laptop runs smooth and I've tuned it up as my main music machine but this issue runs pretty deep and on the surface I can't see a driver issue, no latency issues and no updates pending for anything.  What has my curiousity and perhaps I've not been as detailed as I shoud have been but that this problem does NOT occur and may never have  occurred if I only used headphones.  It only happens when a cable - any cable - is plugged up from my audio device to another device like a mixer or amp.
That's why I explored grouding issues, electrical possibilities etc.  This may be a complex combination of several factors.  Maybe a USB issue, along with a driver and/or even a deep OS issue along with grounding?
Thanks for the link to Windows 8 Tuning Tips for Audio processing but honestly, I had already performed these modifications way before I found that article and read it even before you posted the link.  But thanks for being thorough.
I'd actually be happy if I had to address some clicking or popping - but a complete failure when only cables are connected?  What can I do in the cabling to prevent surges?  I hate to purchase expensive equipment to troubleshoot this, find a surge issue only to have to purchase another laptop, audio interface or something.  Throwing more money at it for only troubleshooting purposes doesn't seem pleasant to me.
I have blue screen logs, memory dump files, etc which have been handed over to Focusrite and still nothing.  I'd like to install Win 10 on it to see if this reoccurs or drop back to Win 7.  I don't know what to do,,,  my first audio interface device to fulfill my dreams of playing live performances and I hit this.. Agh!!!
Frustrated but still willing to troubleshoot,
Thanks,
Chris