Google Hangouts Meet is having audio or video issues when passing the traffic through Cloud SWG
Audio has problems when going through Cloud SWG and using WSSA
Other access methods may have an issue as well.
Cloud Secure Web Gateway (Cloud SWG)
WSS Agent (WSSA)
Explicit proxy may also be impacted
Per Google's document, they recommend that the Google media IP address range is whitelisted, meaning that the traffic goes direct and not through a proxy. To bypass Google Meet traffic from WSS, please do the following:
The above steps can be used for WSSA and explicit proxy connections. If you are using IPsec or proxy forwarding, you will need to create rules on your firewall/router or proxy that will send the traffic direct.
Here is the specific quote from the aforementioned Google document (it has been edited for relevancy):
Step 3: Whitelist Google media IP address ranges
[I]f you have network constraints that require you to restrict traffic, you can whitelist Meet's media servers. These IP ranges are used exclusively for Meet so you can identify video meeting traffic used with your organization's G Suite account and deprioritize Hangouts traffic from consumer accounts.
Whitelist Meet's media servers using the following set of IP ranges:
NOTE: These IP ranges are only for media (audio and video) and do not correspond with the URIs listed above in Step 2.