If you’re running WSJT-X on Windows and suddenly start seeing erratic signal levels, strange noise on the waterfall, or missed decodes that never used to be a problem — you’re not alone.

Recently, I ran into two separate WSJT-X audio issues on Windows 11 that caused fluctuating signal readings, unreliable decoding, and even silent transmissions without me realising it. The good news? Both problems had simple fixes once I tracked them down.

In this post, I’ll walk you through exactly what caused the issues, how to fix them, and how to prevent them from happening again — especially if you operate WSJT-X remotely.

🎥 Watch the full video walkthrough here:

The Symptoms: Erratic WSJT-X Signal Levels & Strange Waterfall Noise

The first thing I noticed was wild fluctuation on the WSJT-X signal meter.

• Signal levels jumping between 19 dB and 50 dB
• Rapid, unpredictable changes
• Strange “glitches” appearing on the waterfall
• Poor or missing decodes

This was especially confusing because:

• The band sounded quiet
• The station hadn’t changed
• WSJT-X had been working fine for months (even years)

Root Cause #1: Windows “Audio Enhancements” Breaking WSJT-X

After some digging, I discovered that a Windows driver update had silently enabled audio enhancements on my radio’s USB audio input.

This is a huge problem for digital modes.

Why Audio Enhancements Break WSJT-X

Windows audio enhancements add:

• Automatic gain control (AGC)
• Noise suppression
• Equalisation
• “Signal improvement” processing

That’s the last thing you want for WSJT-X. WSJT-X expects clean, unprocessed audio & No DSP interference from the operating system. Let WSJT-X do the decoding — not Windows.

Fix #1: Disable Audio Enhancements (Step-by-Step)

This fix applies to Windows 10 and Windows 11.

Step 1: Open Windows Sound Settings

• Open Control Panel
• Set View by → Small icons
• Click Sound

Step 2: Select the Correct Recording Device

• Go to the Recording tab
• Find your USB Audio Codec / Radio Interface
• Right-click → Properties

Step 3: Disable Audio Enhancements

• Go to the Advanced tab
• Untick: “Enable audio enhancements”
• Click Apply

Immediately after disabling this, my audio:

• Returned to normal
• Stopped fading out
• Produced stable signal levels
• Restored reliable WSJT-X decoding

Root Cause #2: Screens Turning Off Killed WSJT-X Audio Devices

Every time my screens turned off, screensaver activated or PC locked WSJT-X would suddenly drop the audio interfaces and with it, mostly transmitting audio. I discovered this while operating remotely. WSJT-X appeared to transmit, the radio keyed up but no audio was actually being sent.

HDMI & DisplayPort Audio Devices

Modern monitors often include, HDMI audio, DisplayPort audio and Built-in speakers you may not even realise exist. Windows sees these as valid playback devices. When displays sleep or change state, Windows may reassign audio, WSJT-X loses its configured device.

Fix #2: Disable Monitor Audio Devices

Step 1: Open Sound Settings

• Control Panel → Sound
• Go to the Playback tab

Step 2: Show Disabled Devices

• Right-click anywhere in the list
• Enable Show Disabled Devices

Step 3: Disable Monitor Audio

Look for entries such as:

• NVIDIA High Definition Audio
• Monitor model names (e.g. Dell U2415)
• HDMI / DisplayPort audio devices

If you don’t use your monitor speakers:

• Right-click each one
• Click Disable

⚠️ This will disable sound from the monitor itself — but prevents WSJT-X from losing audio. If you do need monitor audio – Use dedicated speakers or headphones instead.

Full WSJT-X Setup Guide Available

I’ve also put together a complete WSJT-X setup guide, covering everything from:

• Initial configuration
• Audio levels
• CAT control
• Decoding optimisation

🎥 Watch the full WSJT-X setup video here: