Network Troubleshooting Tools for AV

Network issues in AV systems often manifest as audio dropouts, video glitches, control system timeouts, or devices that simply won't appear on the network. Having a systematic toolkit for diagnosis—and knowing which tool to use when—dramatically reduces troubleshooting time on-site.

Ping

Ping is the most basic network diagnostic tool. It sends ICMP Echo Request packets to a target IP and measures whether a response is received and how long it takes (round-trip time, or RTT).

When to use ping:

• Verifying that a device is reachable on the network
• Checking for packet loss (intermittent dropouts)
• Measuring baseline latency between two points

ping 10.10.1.50          # Basic ping (Windows/macOS/Linux)
ping -t 10.10.1.50       # Continuous ping (Windows)
ping -c 100 10.10.1.50   # 100 packets (macOS/Linux)

For AV troubleshooting, run a sustained ping (100+ packets) to an AV device while an audio dropout is occurring. If you see packet loss or RTT spikes during the dropout, the network is the likely culprit. Consistent RTT under 1 ms on a local network is normal; spikes above 10 ms indicate congestion or switch issues.

Caveats: Some devices (particularly hardened industrial equipment and some Dante devices) have ICMP disabled or deprioritized. A failed ping doesn't always mean the device is down — use Dante Controller or the device's web interface to confirm.

Traceroute (tracert)

Traceroute maps the path packets take from your workstation to a destination, showing each router hop along the way and the RTT to each hop.

traceroute 10.10.1.50    # macOS/Linux
tracert 10.10.1.50       # Windows

For AV systems, traceroute helps identify where latency is being introduced in a routed network. If a Dante flow is passing between VLANs (through a Layer 3 switch), traceroute shows which router interface is handling the inter-VLAN routing and whether it's adding unexpected latency.

In flat Layer 2 networks (single VLAN), traceroute only shows one hop — the destination. It's most useful when troubleshooting routed environments or confirming that inter-VLAN routing is configured correctly.

Wireshark

Wireshark is the industry-standard packet analyzer. It captures raw network traffic and lets you inspect every packet — including Dante audio flows, AES67 sessions, IGMP messages, and control traffic.

Key uses in AV troubleshooting:

• Verify IGMP Join/Leave messages are being sent by AV devices
• Confirm IGMP snooping is working (check if multicast traffic is being flooded to non-subscriber ports by using port mirroring)
• Inspect Dante clock synchronization (PTP) messages
• Capture and analyze dropped or malformed packets
• Verify QoS markings (DSCP values) are being applied correctly

Getting traffic into Wireshark: Most managed switches support port mirroring (also called SPAN — Switched Port Analyzer). Configure the switch to copy traffic from one or more ports to a dedicated mirror port connected to your laptop running Wireshark. This is how you capture traffic you're not generating yourself.

Useful Wireshark display filters for AV:

• igmp — show all IGMP messages
• ptp — show IEEE 1588 PTP clock sync messages (used by Dante)
• udp.port == 4455 — Dante audio traffic
• eth.addr == [device MAC] — all traffic to/from a specific device

netstat and ss

netstat (or ss on modern Linux) shows active network connections, listening ports, and interface statistics on the local machine.

netstat -an              # All connections and listening ports
netstat -s               # Protocol statistics (shows packet errors)
ss -tuln                 # Active TCP/UDP sockets (Linux)

For AV control systems (especially software-based ones running on Windows or Linux), netstat helps verify that the control application is listening on the expected port, that a TCP connection to a device was established, and whether there are connection errors.

iperf3

iperf3 measures actual bandwidth between two points on a network — distinct from the rated speed on the switch port. It tests whether the infrastructure can actually deliver the throughput your AV system needs.

# On server (receiving end):
iperf3 -s

# On client (sending end):
iperf3 -c 10.10.1.50 -t 30 -u -b 500M

For Dante networks, run iperf3 to verify that the available bandwidth on a link is sufficient for your audio channel count. A 64-channel Dante session requires ~288 Mbps. Run iperf3 between the two endpoints and confirm you can sustain that throughput without packet loss.

Dante Controller Diagnostics

Dante Controller (Audinate's free management application) includes built-in network diagnostics:

• Device latency display — shows actual measured latency for each flow
• Clock status — identifies PTP grandmaster and sync issues
• Error indicators — highlights devices with packet loss, latency overruns, or clock errors
• Bandwidth usage — shows total multicast bandwidth per device

For Dante installations, Dante Controller should be your first stop before reaching for Wireshark. It surfaces most common issues (clock conflicts, bandwidth exceeded, latency too tight) in a readable interface.

Switch Monitoring: SNMP and Web GUI

Most managed switches expose status information through a web interface and SNMP:

• Port error counters — high CRC errors, input errors, or output drops indicate a cabling or congestion problem
• CPU utilization — a switch CPU running above 80% may be struggling with multicast processing or STP recalculations
• Interface utilization — check if any uplink is near or over 80% capacity during audio/video activity
• IGMP table — verify that multicast groups are registered on the expected ports

Accessing the switch's web GUI and checking these statistics during a reported dropout is often faster than capturing packets with Wireshark.

Common Pitfalls

• Only checking ping when audio dropouts occur — A successful ping doesn't mean the network is healthy for real-time AV. Ping uses ICMP, which many switches deprioritize. A switch under load may respond to pings fine while dropping time-sensitive UDP audio packets. Use Dante Controller's latency display or iperf3 for a more meaningful test.
• Not having a dedicated troubleshooting laptop — Wireshark and iperf3 require a computer connected to the network. On professional installations, keep a dedicated laptop in your kit with these tools pre-installed and configured.
• Forgetting to configure port mirroring before needing it — When an emergency dropout occurs on-site, having to configure port mirroring under pressure costs time. Consider pre-configuring a mirror port on core AV switches as part of your standard deployment.
• Overlooking switch error counters — A single bad cable causing CRC errors on a switch port will show up clearly in the port error statistics. Check the switch GUI first — it's faster than a packet capture for diagnosing physical layer issues.
• Running Wireshark on a wireless laptop — Wi-Fi adds its own jitter and packet loss, contaminating your capture. Always connect the troubleshooting laptop via wired Ethernet to the mirror port.