Dstar Modem does not detect ThumbDV in Linux

Report preparation

• I used the AI-assisted bug report tool (Help → Support → File an Issue)
• I have attached a support bundle or log file

What happened?

I attempted to enable the D-STAR modem in AetherSDR (v26.7.2). It fails to start with the error message: "Connect a ThumbDV and select it before starting D_STAR".
However, the Linux kernel (Fedora 44) correctly detects and enumerates the ThumbDV hardware as a standard FTDI serial device (/dev/ttyUSB0). No other USB/serial conflicts or permission issues appear in the logs.

The device is a ThumbDV (NW Digital Radio / DVSI USB-3000 equivalent) connected directly to the Linux host.
System details:

AetherSDR version: The device is a ThumbDV (NW Digital Radio / DVSI USB-3000 equivalent) connected directly to the Linux host.
System details:

AetherSDR version: 26.7.2
Qt version: 6.11.1
OS: Fedora 44 (Linux kernel with ftdi_sio module loaded)
Radio: FLEX-6600 (firmware 4.2.20.41343)
Qt version: 6.11.1
OS: Fedora 44 (Linux kernel with ftdi_sio module loaded)
Radio: FLEX-6600 (firmware 4.2.20.41343)

What did you expect?

The D-STAR modem should detect the attached ThumbDV (via serial port enumeration or explicit device selection), initialize the AMBE vocoder, and allow starting D-STAR mode on a slice. This works on other platforms or with equivalent hardware setups, and the OS-level serial device is fully available.

Steps to reproduce

1. Connect ThumbDV (FTDI-based) to the Linux host USB port.
2. Verify detection with dmesg | grep -E 'FTDI|ttyUSB' and ls -l /dev/ttyUSB*.
3. Launch AetherSDR and connect to the FLEX-6600.
4. Navigate to the Digital Voice / D-STAR modem settings.
5. Attempt to select/start the D-STAR modem.
6. Observe the "Connect a ThumbDV..." error despite hardware presence.

AetherSDR version

26.7.2

Radio model & firmware

FLEX-6600 (firmware 4.2.20.41343)

Operating system

Linux

OS version and hardware

Fedora 44 (Linux kernel with ftdi_sio module loaded)