“Your network is causing poor call quality.”
Teams isn't being vague when it shows that warning. There's a specific number Teams is watching, and it crossed a specific threshold. Here's what's actually happening, and how to diagnose it layer by layer — from your device out to the ISP.
What Teams is actually measuring
Teams monitors a metric called the Concealed Sample Ratio. When you're on a call and your network drops audio packets, the receiving Teams client doesn't play silence — it interpolates. It synthesizes audio frames from the packets it did receive, using error- concealment algorithms.
This works for a few percent of dropped packets without anyone hearing a difference. But when the concealed sample ratio climbs past about 1.72% — roughly 1 in 60 audio frames being invented rather than received — the audio starts to sound robotic, words clip, conversation gets choppy.
That 1.72% threshold is the trigger for the "Your network is causing poor call quality" warning. Teams is telling you, fairly precisely, that your line is dropping packets faster than the codec can paper over.
What causes packets to drop on a Teams call
Five common causes, in roughly decreasing order of how often each turns out to be the answer:
Wi-Fi link quality on your end
Wi-Fi loss is real even when speed tests look fine. The radio environment can degrade for short windows (microwave running in the kitchen, neighbor's network on the same channel, signal dropping when you walk between rooms). Each drop is a few hundred milliseconds of lost packets — easily enough to push the concealed ratio over the threshold.
The fastest test: plug in via ethernet for one call and see if the warning goes away. If it does, your Wi-Fi link is the problem. The standard fixes apply — 5 GHz instead of 2.4, move closer to the access point, disable Bluetooth on the same machine to eliminate coexistence interference.
Bufferbloat on your home router under load
If anything else on your network is doing heavy traffic — cloud backup, software updates, video streaming, large downloads — your router queues packets. The Teams audio packets get stuck behind the queue. The result is that even though your speed test says you have gigabit, your Teams call is fighting for the next slot to send its packet, and the wait time spikes.
Two paths. First, identify what else is using your connection and pause it for the call. Second, enable Smart Queue Management (SQM / fq_codel) on your router if your firmware supports it — this de-prioritizes bulk traffic so real-time packets like Teams audio don't get stuck behind them.
Corporate VPN routing your traffic through a slow gateway
If your company forces all traffic through a VPN before it reaches Teams (split tunneling disabled), the VPN gateway becomes the bottleneck. Teams traffic goes from your home to the VPN gateway and then back out to Microsoft's servers — adding latency and a potential congestion point you can't see.
If your company supports split tunneling for Teams (Microsoft publishes guidance for this), ask IT to enable it. Teams traffic skips the VPN, goes direct to Microsoft, latency drops, call quality usually recovers immediately.
ISP packet loss on the path to Microsoft
Less common but real. Your ISP's peering with Microsoft's network goes through specific interconnection points. If one of those points is congested, you'll see packet loss on the specific route to Teams' servers but not on your speed test to a nearby Ookla server.
Run a traceroute to teams.microsoft.com from your machine. Look for hops where the round-trip time spikes or shows asterisks (lost replies). If the spike is on a hop labeled with your ISP's name, the problem is on your ISP's side. The ISP escalation playbook applies.
Microsoft's side, briefly
Teams itself has occasional service incidents. Microsoft's status page (status.office365.com) shows when this is the case.
If status.office365.com is reporting a Teams incident and your warning appeared at the same time, wait it out. Resist the urge to debug your home network when the problem is upstream.
The layered diagnostic, in order
Don't try to fix this from the top. Each layer is faster to check than the next, and ruling each one out tells you which layer is actually the problem.
- Check Microsoft's status page first. status.office365.com. Takes ten seconds. If Teams is having a service incident, you've found the cause without doing any home-side work.
- Try a wired call. Plug a Cat6 cable from your laptop or desktop to the router. Disable Wi-Fi on the device. Make a test call. If the warning goes away, your Wi-Fi was the cause.
- Run the StabilityPulse stability test. Visit stabilitypulse.com. The Teams readiness card in the results will tell you whether your jitter, loss, and loaded latency are within Teams' published thresholds. If it shows red on Teams, the network is the problem; if it shows green, the network is fine and something else is wrong (look at VPN or Microsoft-side issues next).
- Test on a hotspot. Disconnect from your home network entirely. Connect to your phone's hotspot (use ethernet from phone to laptop via a USB-C dongle if your phone supports tethering well). Make a test Teams call. If it works perfectly on the hotspot, your home network is the problem. If it's still bad on hotspot, the problem is either Microsoft or your work VPN.
- Check VPN behavior. If your work requires a VPN, disconnect from it briefly (assuming policy permits this) and make a personal Teams call. If audio is suddenly clear off-VPN but bad on-VPN, your IT department needs to enable split tunneling for Teams.
What the “Teams Network Performance” view tells you
Inside a Teams call, click the call quality indicator (typically top right) — Teams shows a panel with five metrics: latency, jitter, packet loss, and per-stream quality. Two things to look at:
- Jitter above 30 ms: exceeds Teams' acceptable threshold. Almost always points to Wi-Fi link quality or upstream congestion.
- Packet loss above 1%: exceeds Teams' acceptable threshold. Points to either Wi-Fi (drops during the call) or routing/peering issues if it's consistent across many calls.
If both jitter and packet loss are in spec but the warning still appears, you're hitting the concealed sample ratio threshold through micro-bursts that the averaged metrics don't catch. That's typically buffer- bloat on your home router under load — Smart Queue Management on the router is the canonical fix.
The Wi-Fi fixes that actually matter for Teams
If the wired-vs-Wi-Fi test showed Wi-Fi is your problem, the highest-impact Wi-Fi fixes for call quality specifically:
- Force 5 GHz. 2.4 GHz is more congested, has more interference, and packet loss rates run substantially higher in any apartment building. If your laptop is on 2.4 GHz, switch.
- Move closer to the access point during calls. Even a single wall between you and the AP can drop link quality enough to push concealed samples over the threshold. If you have to take a call from a back room, a Wi-Fi extender or mesh satellite (with ethernet backhaul if possible) helps.
- Disable Bluetooth audio during important calls. Bluetooth and 2.4 GHz Wi-Fi share spectrum, and on combo chips (most laptops) active Bluetooth audio throttles Wi-Fi throughput visibly. Use wired headphones for calls you can't afford to drop.
- Check power management on the Wi-Fi adapter. Windows aggressively power-saves the Wi-Fi radio on laptops, and the throttling shows up first on real-time workloads like Teams. Disable in Device Manager → Network Adapters → your Wi-Fi adapter → Properties → Power Management.
For the full per-device Wi-Fi diagnostic — the case where Wi-Fi works on every other device in the same room except yours — see the PC Wi-Fi guide.
When Teams is the problem and your network isn't
Three signals that the network is fine and Teams is misreporting:
- Same-time calls on Zoom, Meet, or Discord work fine while Teams shows the warning. This is a Teams-side routing or service issue, not a network problem.
- The warning appears within seconds of joining every call, regardless of network state. Teams sometimes caches a bad-quality verdict across sessions and re-displays it incorrectly. Restart the Teams client fully (quit, not just close the window).
- Microsoft has acknowledged a known issue on status. office365.com. The warning is responding to a measurement that the Microsoft side is generating incorrectly.
In each of these cases, no amount of router or Wi-Fi tuning will fix the warning — the diagnosis is correct that Teams is showing the warning, and the diagnosis is also correct that your network isn't the cause.
If this is happening to your whole team
If multiple people on the same call are seeing the "poor call quality" warning simultaneously, the problem is upstream of all of you — almost certainly Microsoft's side. Multiple users hitting concealed-sample-ratio thresholds at the same moment from different networks points at the Teams service, not coincidentally-bad home networks.
If multiple people on the same physical network are seeing it (everyone in the same office, or the whole family at home), the problem is shared infrastructure — router, modem, or ISP. The diagnostic path is the same as for any one person, but the fix benefits everyone once it lands.
Sibling reading
- Network seems fine but specific device is bad: Per-device Wi-Fi diagnostic.
- Network is consistently slow and ISP says everything's fine: ISP escalation playbook.
- Test what Teams readiness actually looks like for your line right now: StabilityPulse stability test.