I have disabled ASIOguard on my system at home. I have duplicate setups at my studio and at home: each location has a host PC (HP 810) running a VEP server + Cubase Pro 8 and a slave PC (Dell 7500) running another VEP server. There is only differences between the 2 locations are the audio interfaces: my studio setup has the Fireface UC RME (USB), and at home I have the Yamaha MR816CSX (firewire).
Every week I work some in the studio and some at home (I sync my projects through Google Drive & Dropbox). My work is all MIDI, and I have around 500 MIDI tracks in my template (organizational folders and group/fx tracks push the track count to 900+).
At my studio, I left ASIOguard running - default after Cubase 8 upgrade. Everything ran just fine there, but when opening the same project at home, I experienced dropouts and crackles. As soon as ASIOguard was disabled at home, everything was perfect.
As a side note, I found a utility for the MR816CSX that increased the firewire buffer of the unit. The factory setting buffer size is set to "small!"
Hopefully, that helps someone or provides another thing to look at when troubleshooting.