Hummingbird seems to be having real issues (defender to a leser extent)

Hi Gurus,

In the last few days on a number of sites, performance has been hit hard (page load times on admin side and front end). The sites are hosted on SiteGround. After doing the usual all plugins deactivate and step wise reactivate, it seems to me that Hummingbird, once activated drags my site down. I start getting Gateway Timeouts on every single Admin activity. I've tested the other plugins, none of them seem to affect performance.

With Defender, I've been getting a constant "cURL error 6: name lookup timed out" on the dashboard page.

If you can take a look I would be grateful. Sites I've noticed problems on:
uplyft.ca <-- biggest problems
reliable.vrwebsitedeveloper.com

Thank you kindly,