The usual suspects, in order
The network, not Teams: voice on WiFi without QoS produces the classic robotic/drops pattern — same physics as any VoIP quality issue; wired-vs-wireless is test one, router prioritisation is fix one. Headsets and devices: an unreasonable share of 'Teams is broken' is a Bluetooth headset with old firmware or Windows picking the wrong mic — certified devices and a settings check clear it. Calling configuration: external calls failing or misrouting usually traces to the calling route setup — Operator Connect assignments, Direct Routing SBC rules, dial plans, queue licensing. Genuinely Microsoft: it happens — service incidents show on the 365 health dashboard, and the correct move is knowing it's them, fast, rather than rebooting routers all afternoon.
Fix it once, then keep it fixed
The durable version: QoS configured end-to-end for Teams media, certified audio devices as policy, calling config documented (so the fix survives the person who made it), and quality monitoring through the Teams admin call-quality data — which turns 'people are complaining' into 'the Leeds office's WiFi is the pattern'. This is precisely the layer our Teams Phone support owns: one number to call, whether the fault is network, device, config or Redmond — and if it's Redmond, we're the ones chasing the ticket, not you.
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Frequently asked questions
Why are Teams calls fine but external calls poor?
Internal calls stay on Microsoft's network; external calls traverse your calling route — pointing the diagnosis at the route configuration or the local network edge. Both are fixable, quickly.
Do we need special headsets for Teams?
Certified devices genuinely behave better — firmware, button integration and audio processing are tuned for it. It's the cheapest quality upgrade available.
How do we know when it's Microsoft's fault?
The 365 service-health dashboard, plus experience of what platform incidents look like versus local ones. Part of support is telling you 'it's them, here's the incident, here's the workaround' in minutes.