'BufferSwitch' function error

[george]

good morning,
I just opened a reaper project - really heavy with lots of plugins & media items - and right after tried to do 'Save as' with a different filename.
This is the error message I got from the ASIO Lynx driver:

"The application 'reaper' failed to return from the 'BufferSwitch' function within the alloted time.
This is a serious bug in the application and you should notify the application manufacturer of this problem so it can be corrected immediately.
You may wish to disable hyper-threading (if on) to see if this solves the problem with this application"

and a screenshot here:
https://postimg.org/image/76sycbufx/

This has never happened before, I don't know how to reproduce it, but if I can help somehow let me know.

My set-up is:
Windows 7 Professional SP1 64-bit
Reaper 5.25/x64 rev dvb808
audio interface details:
Lynx AES16e firmware v14.0
LynxWDM.dll v2.00 build 23a
LynxV264.sys v2.00 build 23a