A flash command before issuing a status command fails with "pipe error"

[OpusElectronics]

If the first command sent to the WCH-Link adapter (when it has been plugged to USB) via wlink is a 'flash' command, it fails in the following way:

[INFO] Connected to WCH-Link v2.9(v29) (WCH-LinkE-CH32V305)
Error: USB error: Pipe error

Caused by:
    Pipe error

If we issue a 'status' command first, it works fine, and subsequent 'flash' commands all work until the WCH-Link is unplugged/replugged to USB.

On Linux, if that makes a difference.

[andelf]

Could you provide wlink -vv output?