Thanks everybody for your responses. Some very useful information.
To answer a couple of questions posed, the Roon Core is running on my PC (desktop) and I’m using a Samsung Galaxy Tab A8 as the controller. This connects via my AT&T Fiber wi-fi (300Mbps), so I’m pretty sure that’s not a bottleneck.
The Hermes (to re-iterate) is connected to the Morpheus via I2S ethernet cable. I do have the USB module and could change back to it if there would be any advantage to that. For those of you who aren’t familiar with this particular DAC, the USB connection uses the same slot as the I2S ethernet connection, but you have to remove one module and replace with the other if you want to switch formats for this input.
As for using the SD slot to change platforms, I haven’t experimented with this yet--it’s a bit complicated and to be honest, I’m not having a lot of success understanding Sonnet’s documentation on the subject. I guess some experimentation is in order here.
If it’s my router that’s causing the problems, I don’t really know what to do about that. Not really versed in the technology of wi-fi signals and how they might vary.
From the opinions expressed here, it seems that Roon has many great advantages and the majority opinion is that you all seem to like it. So I guess it’s worth making the effort to try to solve these issues before giving up entirely. So at this point, mind still open.
Oh, and yes I DID make use of Roon's knowledge base and support forum when setting everything up, and it proved very helpful. I searched for this particular problem through those sites but didn't find a remedy I thought was useful.
Thanks again for your input.