Fix TCI TX Silent on Windows or Linux without PipeWire¶
TCI TX audio is routed through a dedicated dax_tx stream slot inside AetherSDR's TCI server, independent of the Windows SmartSDR DAX2 audio device path and independent of PipeWire. This means TCI TX should work on all platforms without any special configuration. This page helps you confirm the TCI server is set up correctly and the TX gain is not the cause of silence.
Before you start¶
- AetherSDR must be connected to the radio. The TCI applet requires an active radio connection.
- The third-party application sending TCI TX audio (for example, a digital-mode program) must be configured to connect to AetherSDR's TCI server, not to SmartSDR DAX2 or any other audio device.
- Make sure you are running AetherSDR v0.9.5.1 or later. Earlier versions had a platform-dependent TX audio policy that could block TX audio on Windows and Linux without PipeWire.
Steps¶
- Click the TCI tray button on the right sidebar to open the TCI Server applet.
- Check the server status label next to the Port field.
- If it reads
(stopped), click Enable to start the server. - If it reads
(port in use), the chosen port is already bound by another process. Change the value in the Port field to a free port (valid range: 1024–65535; default:50001), then press Enter and click Enable. - Confirm the status label shows
:<port> (N clients)with at least one client connected. If your TX application is not shown as a connected client, check its TCI host and port settings and ensure they match the Port field value. - Look at the TX row in the applet. Check the slice-assignment label next to the TX meter.
- If it shows
—, no slice is currently designated as the TX slice. Use the radio's slice controls to assign a TX slice. - If it shows
Slice <letter>, the TX path is active. - Drag the TX gain+meter slider to confirm it is not set to
0.0. The default is0.5(valid range: 0.0–1.0, persisted asTciTxGain). A value of0.0produces silence regardless of platform. - Key the transmitter from your third-party application and watch the TX gain+meter for level movement. If the meter shows activity, audio is reaching the server and the radio should be transmitting.
What each control does¶
| Control | Default | Valid range |
|---|---|---|
| Port | 50001 |
1024–65535 |
| Enable | Off | On / Off |
| TX gain+meter | 0.5 |
0.0–1.0 |
| RX1 gain+meter | 0.5 |
0.0–1.0 |
| RX2 gain+meter | 0.5 |
0.0–1.0 |
| RX3 gain+meter | 0.5 |
0.0–1.0 |
| RX4 gain+meter | 0.5 |
0.0–1.0 |
| ## Tips |
- Out-of-range port values snap back to
50001automatically. - If you want the TCI server to start every time AetherSDR launches, enable
Settings > Autostart TCI with AetherSDR. This sets theAutoStartTCIflag and also checks Enable on startup. - The TX meter uses fast attack and slow decay smoothing, so a brief transmission will keep the meter visibly elevated for a moment after audio stops. No movement at all during a keyed transmission confirms audio is not arriving from the client.
Troubleshooting¶
- Status shows
(port in use)and Enable snaps back to off — Another application is bound to that port. Enter a different port number in the Port field, press Enter, and click Enable again. - Status shows the correct port and client count, but the radio is not transmitting audio — Confirm the TX slice label in the TX row shows
Slice <letter>and not—. If it shows—, designate a TX slice from the main UI. Also confirm the TX gain+meter is above0.0. - Third-party application cannot connect — Verify the application is pointed at
localhost(or AetherSDR's host IP) and the port number matches the Port field. Confirm no firewall rule is blocking the port. - TX meter shows no movement despite the client being connected and keyed — The client application may be sending audio to a system audio device rather than over the TCI WebSocket. Check the client's audio output or TCI audio routing settings. AetherSDR does not use the Windows DAX2 audio device for TCI TX; audio must arrive over the WebSocket connection.