I also have AMD RX590 driver version 19.2.1 (latest 2019-02-04 I think) and having the same problem. Actually I have it as an eGPU in a Akitio Node case. But that aside, as described below, I experience the same situation Intel's Hades Canyon which also contains a discrete graphics processor.
I already brought this issue of hanging at 'loading waveform monitor' to the attention of Peter Chamberlain in another related post on forums here, but it might be worthwhile repeating here since it is a related issue and also to bring to the attentijon of Dwaine Maggart as well.
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Well, frankly, I am having that exact same problem, disappointingly and sorry to say, as I want to standardize on Davinci Resolve. But with a reliability that it may work one day and then subsequent to a new upgrade, or graphics driver, or whatever, it won't work is a reliability I can not contend with when in the middle of the project. If you recall, on more then one occasion I suggested making a basic, intermediate, and advance level of Resolve for new users. That might very well carry over to the level of complexity and system demands too so that if an advanced level of Resolve is too demanding, at least a user can backtrack to intermediate or basic level of system demands to still be able to be productive. But I don't see that becoming a reality any time soon if it ever happens.
So with the 'loading waveform monitor' issue, I spend more time trying to figure out a resolution to the problem rather then being truly productive. Troubleshooting, the auto mechanic so to speak. I've uninstalled and reinstalled more then once for sure. Oh, and BTW, I DO have a more modern machine. Intel's Hades Canyon Core i7 released around mid 2018 with the AMD discrete graphics chip. My drivers are all up-to-date too through Intel's Driver & Support Assistant.
https://www.intel.com/content/www/us/en ... stant.html
It sniffs out my entire system online and if there are components that need updating, Intel allows me to download and automatically update as necessary.
So, although Brantley's situation might be needing a more modern computer that surely is not my case. I reckon then, until the problem eventually goes away, if it goes away, I need to carry on with another tool, i.e., Shotcut, etc., which, BTW, loads with no problem and quite quickly too.
FYI, am running, (frustratingly trying to) Resolve 15.2.3, the latest.
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