Anyone know what changed in Wavelab 10 VST3 handling? SOLVED

[Nonlinear]

One of my existing VST3 iPlug1 builds, that passes "pluginval" and Steinberg's VST3 validator tool and has been working for a long time, crashes the new Wavelab 10. This same plugin works perfectly in Cubase 10 and Wavelab 9.

The plugin loads and runs fine in the Master section of Wavelab 10 but crashes if used in the clip, track or output sections. The crash occurs the first time playback is stopped. The plugin loads and works properly up until that point.

I understand Steinberg changed the audio engine for WL 10 and, IMO, something broke in the process. I reported this to PG at Steinberg but he automatically assumes it is not a problem in Wavelab. One of the advertising claims for WL 10 is "improved third-party VST support" - but in my case that is FALSE!

Will try to debug this but, in the meantime, anyone else here having issues with VST3 in Wavelab 10?

BTW - the VST(2) version of this same plugin works perfectly