Sounds familiar, including the initial ‘flash’. Like reports all over the forum, I intermittently suffer from very slow / slow /sluggish retrieval of search results (since Roon 1.6) when Qobuz account is activated. It has been as bad as 30-40 seconds at least. Sometimes, trying again a couple of times results in a noticeable improvement, often it doesn’t.
Repeated checks - on potential local network or Internet connectivity /speed issues - when Roon searches slow to a crawl, have shown nothing out of the ordinary. The native Qobuz app does not suffer any problems with either search or playback when the Roon search result retrieval slowness manifests.
Other relatively bandwidth hungry (video) streaming services play happily. With Qobuz disabled, results are quick as of old and there are no playback issues. Switching between my Internet providers’ own DNS servers and Google or Cloudflare makes no discernable difference. I am based in the UK, down spead typically ca 35 Mbps, up ca 8Mbps.
Scanning the quite sizeable number of reports (some angry, some relaxed, some mater-of-fact), and support requests in recent weeks and months, my instinct and bet would be that the issue is further upstream, closer to Roon’s infrastructure.
I actually like that idea much more than finding out that my own network infrastructure and Internet connectivity is below par for Roon+streaming service. Am simply hoping it’s within Roon’s control and they can solve this in the not to distant future. Actually, I believe they will. If not, my stop-gap, reluctantly, would probably be to revert to using Roon with local library only.