Measure, do not guess
Check latency, jitter and packet loss during the busy period. A speed test taken when the office is quiet can miss the actual issue.
Fix the local network
Use wired connections where practical, reliable PoE, suitable QoS and clean switching. Voice over weak or congested Wi-Fi needs a roaming design.
Review edge and provider settings
Firewall handling, SIP timeouts, NAT and provider routing can affect one-way audio, dropped calls and delayed setup.
Project checklist
- Record the time and direction of affected calls
- Compare wired and wireless handsets
- Test during peak business load
Practical takeaways
- Define the operating requirement before choosing products
- Document interfaces, failure behaviour and ownership
- Test the completed system and keep records for support