Phone call connects but neither party can hear each other. Anyone having the same issue?

Last week we started noticing complaints from our staff that they were not hearing anything one some phone calls. If a person outside the company called a staff, the staff would pick up the call but not hear anything. There’d be dead silence. Staff would hang up and call back. Then, both parties could hear each other. We have noticed that the issue has become pronounced. We have heard a lot more complaints. Regardless whether it’s an outbound call or inbound call or inter-company call, the dead silence issue appears every now and then for many staff members. The ones who make/receive a bunch of calls throughout the day are hurting the most.

Zoom meetings also take over 30 seconds before they connect. We have noticed the dead silence issue from laptops, phone apps, over wired network, wireless network, and in different geographies. Has anyone else noticed this behavior lately? If so, how did you resolve it?

We have a support ticket open. I thought I’d ask if others had inputs.