Cubase 10.5 VST3 Silence Flags bug

I have added support for the VST3 ‘Silence Flags’ to my plugins, but they are crashing with an assertion due to the input buffer not being silent.

Steinbergs documentation states: “The host has the responsibility to clear the input buffers (set to zero) when it enables the silence flags”.

However I launched Cubase Studio 10.5 with a breakpoint in the process method.
The DAW passes my effect the silence flag: 0x00000000ffffffff which I interpret to mean “All inputs are silent”. However looking at the input buffers, they are filled with the following alternating pattern (which is not zero):



So If am correct - Either the documentation is wrong, or Cubase Studio 10.5 has a defect?

Any guidance is much appreciated,

The documentation is wrong. The buffer is set to a value identical to silent (something near zero).
This is done to prevent de-normalization .

Thanks, I thought it might be for denormalization.

What I’ve done in my plugin, is when Cubase sets the silent flag I substitute the DAW-provided buffer with a pre-prepared buffer full of zeros. This prevents my plugin from asserting.

(my plugin disables denormals via an FPU flag anyhow).