I have just had a play with this too see if it is suitable for a project I am working on.
I had a couple of crashes which this should fix.
When scrubbing, if cycling speed fast whilst at the live point, then it could crash as one of the fields pulled from the file could be null.
After a while I got a crash in receive_impl(). with something to do with framebuffer being null. It all looked ok, but im pretty sure std::queue isnt thread safe, so that is a speculative fix
I have just had a play with this too see if it is suitable for a project I am working on. I had a couple of crashes which this should fix.