Voice mode: "Connection closed: code 1006" on Linux

Bug Description

Voice mode (/voice) fails with WebSocket error: Voice stream error: Connection closed: code 1006

Steps to Reproduce

1. Run /voice in Claude Code
2. Voice mode enables ("Hold Space to record")
3. Immediately or shortly after, error appears: Voice stream error: Connection closed: code 1006

Environment

• Claude Code: 2.1.69
• OS: Ubuntu 24.04.4 LTS, Linux 6.17.0-14-generic x86_64
• Node: v20.11.1
• Audio: PipeWire 1.0.5, sox 14.4.2, rec works correctly
• Network: Direct connection (no VPN/proxy), API reachable

Troubleshooting Done

• Verified mic works (rec and arecord both record successfully)
• PipeWire running, audio sources detected
• No proxy env vars set
• pactl list sources shows active capture devices
• Updated to latest Claude Code version
• Confirmed curl https://api.anthropic.com returns 404 (expected, API reachable)

Expected Behavior

Voice mode should establish WebSocket connection and accept voice input.