A technician receives several complaints from the same office about VoIP calls sounding broken up,...

VoIP traffic is highly sensitive to latency, jitter, and packet loss, even when overall internet bandwidth appears sufficient. According to CompTIA Core 1 (220-1201) networking and VoIP troubleshooting objectives, normal speed test results do not guarantee good VoIP performance because speed tests measure throughput, not real-time traffic prioritization.

In this scenario, users experience choppy audio and lag, which are classic symptoms of voice packets competing with regular data traffic during periods of network utilization. Enabling Quality of Service (QoS) on the router allows the network to prioritize VoIP traffic over less time-sensitive data such as web browsing, file downloads, or streaming. This ensures voice packets are transmitted with minimal delay, improving call clarity and reliability.

Configuring PoE only supplies power to VoIP phones and does not affect call quality. Changing wireless encryption standards does not resolve latency or prioritization issues. MAC address filtering is a security feature and has no impact on VoIP performance.

CompTIA emphasizes QoS as a key solution for resolving VoIP performance issues in environments where bandwidth exists but voice traffic is not properly prioritized.