CPU Overload error - change from C10.5 to C11 (solved)

In C11 I’m starting to see this error pop up every now and again when playing back audio and editing FX.

“CPU Overload/Audio drop out detected”

Audio playback doesn’t stop and NO clicks or pops are heard - you just need to click ok to continue - just annoying

I’ve NEVER seen this error before (We’ve all seen a similar error on export I suspect)

I went back and tried the same things on C10.5 and the error doesn’t occur, even doing the same actions that trigger the error in C11. Same preferences etc etc.

Is this a new error ?
is it more sensitive than before ?
Has the audio engine some new bugs ?

I’m running low buffers and I know I can probably avoid it by increasing them but it points to something different or broken in C11

further info:

Buffer size has nothing to do with it - even on max buffers the error remains.

Simple repro:

Blank project
press play
F4 - audio connections
add an input bus

That triggers the error for me every time

no error in C10.5 or N10.3

And yes I know you might expect an error adding an input bus whilst playing but that’s just an example - I occasionally get the error whilst doing other, more normal things

win10 - RME raydat

and here’s the answer:

preference “Warn on Processing Overloads” was ON in C11 - assume it defaults to this as all the other preferences were copied across from C10.5 apart from that one ?

case closed