Since the release of these latest builds, I have no news about users that have reported this problem again, so in any case, please update your Octane build to them. I'm not sure if a repro scene is going to help, I have several scenes from other users here, but I've never been able to reproduce the problem.
The fixes included in the latest Octane plugin build should be theoretically enough to be sure that in no case the scene data is altered in any way from the plugin side, at least from all the data I have from the HDK docs and the SideFX help, although nobody knows exactly how something like that was possible in the older Octane plugin builds ... I mean, it could be a bug in an HDK function, but now the plugin is not using any function that could change the scene spare parmeters, that is the source of the problem.
Computer Graphics Software Developer
Octane plugin development and support: LightWave and Houdini