Studio 15 timeline 'garbled'

I had been using Resolve 15 lately and upgraded to latest Studio version yesterday.
Never had this problem before: Half of the time I turn on Studio my timeline gets 'garbled' up like this (attached pic). The timeline cursor also becomes a black block.
I turn on/off again, reboot and the problem persists. It's seemingly random. Anyone have any ideas what's going on?
Thanks in advance
Never had this problem before: Half of the time I turn on Studio my timeline gets 'garbled' up like this (attached pic). The timeline cursor also becomes a black block.
I turn on/off again, reboot and the problem persists. It's seemingly random. Anyone have any ideas what's going on?
Thanks in advance