Diagnose audio underruns and jitter¶

Use the Network Diagnostics dialog to read live audio buffer health, underrun counts, arrival gap timing, and jitter estimates. This helps you identify whether audio dropouts are caused by a starved buffer, bursty packet delivery, or network jitter.

Before you start¶

AetherSDR must be running. The dialog does not require an active radio connection, but the audio indicators are only meaningful while a radio is connected and streaming audio.
Reproduce the audio problem before opening the dialog so the counters and peak values reflect the fault condition.
The dialog window geometry is saved and restored automatically between sessions.

Steps¶

Click Settings > Network... to open the Network Diagnostics dialog.
Use the tab bar at the top to select the view you need:
Overview – Health cards and summary time-series charts.
Details – Scrollable grid of all labeled metrics.
Latency – RTT, arrival gap, and jitter chart.
Rates – Per-stream incoming bitrate chart.
Packet Loss – Per-category packet loss percentage chart.
Audio – Playback buffer fill and underrun rate chart. Includes per-stream RX audio diagnostics showing feed rate, deficit, late packets, packet class code, and stream health for each active audio stream.
Logs – Live tail of the AetherSDR log file.
On the Details tab, locate the Audio Playback group.
Read RX Buffer Now to see how many bytes (and milliseconds) of audio are currently held in the playback buffer.
Read RX Buffer Peak to see the highest buffer fill recorded since the dialog was opened.
Read Underruns (total) to see the cumulative count of buffer underruns since the audio engine started.
Read Underruns (last sec) to see how many underruns occurred in the most recent one-second window. A non-zero value here while audio is actively streaming indicates an ongoing problem.
Read Audio Arrival Gap to see the current inter-packet arrival interval. A value significantly larger than the expected packet period indicates bursty delivery.
Read Max Arrival Gap to see the worst-case arrival gap recorded since the dialog was opened.
Read Network Jitter to see the smoothed jitter estimate for the audio stream.
If underruns are rising but RX Buffer Now stays near zero, the buffer is starving — see the tips below.
Click Close when finished.

What each control does¶

Tabs¶

Tab	Behavior
Overview	Shows four health cards (Status, Latency, Packet Loss, Audio Buffer) and four time-series graphs (Latency and Jitter, Recent Packet Loss, Total Stream Rates, Audio Buffer).
Details	Scrollable grid with labeled values for Network Status, Incoming Stream Rates, Packet Loss, and Audio Playback groups.
Latency	Full-width time-series graph of RTT, arrival gap and jitter in ms.
Rates	Full-width log-scale time-series graph of per-stream incoming bitrates (RX total, Audio, FFT, Waterfall, Meters, DAX) in kbps.
Packet Loss	Full-width time-series graph of packet loss % per stream category.
Audio	Full-width time-series graph of playback buffer fill (ms) and underruns/s. Includes per-stream RX audio diagnostics showing feed rate, deficit, late packets, packet class code, and stream health for each active audio stream.
Logs	Live tail of the AetherSDR log file, filtered by category checkboxes. Syntax-highlighted by log level and category name. Timeframe selector is hidden while this tab is active.

Controls¶

Control	Type	Default	Behavior
Timeframe	Combo box	5 minutes	Selects how far back the time-series charts display history. Options: 1 minute, 5 minutes, 15 minutes, 1 hour, 1 day, 1 week. Shown in the top-right corner of the tab bar; hidden when the Logs tab is active.
Filter Categories (Logs)	Checkboxes	–	Per-category checkboxes filter the log view. Includes a General (default) category plus all registered LogManager categories.
Select All (Logs)	Push button	–	Shows all log categories in the viewer.
Deselect All (Logs)	Push button	–	Hides all log categories from the viewer.
Live / Paused (Logs)	Toggle button	Live	When Live, the viewer auto-scrolls to newest output. Scrolling up auto-pauses; clicking Live resumes and jumps to the tail.
Close	Push button	–	Closes the dialog.

Indicators¶

All indicators refresh once per second.

Indicator	Meaning
Status	Overall link quality, color-coded green → red. States: Excellent, Very Good, Good, Fair, Poor.
Target Radio IP	IP of connected radio, or "Not connected".
Selected Source	Local NIC/bind path used for the connection.
Local TCP	Local TCP endpoint.
Local UDP	Local UDP endpoint.
First UDP Packet	Whether the first UDP packet has been received since connect. States: Yes, No.
Latency (RTT)	Current round-trip time.
Max Latency (RTT)	Highest RTT seen since connect.
Audio / FFT / Waterfall / Meters / DAX rates	Per-category ingress rate in kbps.
Total RX / Total TX	Aggregate bytes per second in each direction.
Audio / FFT / Waterfall / Meters / DAX drops	Per-category dropped-packet counts and percentage.
RX Buffer Now / Peak	Current and peak audio buffer fill in bytes and ms.
Underruns (total / last sec)	Audio underrun counters.
Audio Arrival Gap / Max Arrival Gap	Inter-packet arrival timing.
Network Jitter	Smoothed jitter estimate of audio stream in ms.
Log path label	Shows the full path of the log file being tailed.
Feed Rate	Current audio feed rate for each active stream.
Deficit	Current audio deficit for each active stream.
Late Packets	Count of late packets for each active audio stream.
Packet Class Code	Packet class code for each active audio stream.
Stream Health	Health status for each active audio stream.

Using the Logs tab¶

The Logs tab provides a live tail of the AetherSDR log file directly inside the Network Diagnostics dialog.

Click the Logs tab. The Timeframe selector in the top-right corner is hidden while this tab is active.
The log path is shown at the top of the tab. This is the full path of the file being tailed.
Use the Filter Categories (Logs) checkboxes to include or exclude specific log categories. The General category is available by default; additional categories appear as LogManager registers them.
Click Select All (Logs) to enable all categories at once. Click Deselect All (Logs) to hide all categories.
The viewer is in Live mode by default and auto-scrolls to the newest output. Scroll upward to pause auto-scrolling; the button changes to Paused. Click Live to resume and jump back to the tail.
Log entries are syntax-highlighted by log level (debug, info, warning, critical) and category name.

Tips¶

Underruns rising, buffer near zero: The audio stream is not arriving fast enough to keep the buffer filled. Check the Audio rate in the Incoming Stream Rates group and compare it to the expected bitrate. A very low or zero Audio rate means packets are not arriving at all.
Zero packet loss but still getting underruns: The Packet Loss (Sequence Gaps) group counts only missing VITA sequence numbers. Packets that arrive late rather than missing will not increment the drop counter but will still cause jitter and underruns. Use Audio Arrival Gap and Network Jitter to detect this condition.
Large Max Arrival Gap with low average gap: This indicates occasional bursts of delayed packets rather than sustained loss. Isolate the network path to the radio and check for competing traffic.
RX Buffer Peak is very low: The buffer never built up a useful reserve. This makes the stream sensitive to any delivery variation. Check the network path and consider whether other heavy traffic is competing on the same link.
Investigating unexpected disconnects or errors: Open the Logs tab and enable the relevant LogManager categories. Use Filter Categories (Logs) to focus on the category of interest, then reproduce the fault while the viewer is in Live mode.
Per-stream RX audio diagnostics: On the Audio tab, review the feed rate, deficit, late packets, packet class code, and stream health for each active audio stream. This helps identify individual stream issues that may not affect other streams.

Troubleshooting¶

All audio indicators show zero or no data — The radio is not streaming audio. Confirm the radio is connected and a receiver slice is active.
Underruns (last sec) is non-zero but Underruns (total) is small — The problem is intermittent. Leave the dialog open and wait for a longer observation period. Watch Max Arrival Gap for evidence of periodic bursts.
Network Jitter is high but Audio drops show zero — Packets are arriving late rather than being lost. Jitter directly reduces the effective buffer margin. Check for other UDP traffic competing on the same interface.
Logs tab shows no output — Confirm the log file path shown at the top of the tab is accessible. If no categories are checked, click Select All (Logs) to restore visibility.