Comment 30 for bug 1708043

Quoted from Lenovo:

Yoda-1.0 (X1 Carbon 5th) only have Alpine Ridge AR-DP B1 (Device ID = 0x15D3) model.

Lenovo Thunderbolt Dock also uses it.

0x1578 is previous Alpine Ridge chipset (2015), P70 (Payton) only has it.
Or other vendor dock may have it (Ex: HP Elite Thunderbolt 3 65W Dock etc.).

AR_HR_4C_XHC

Alpine Ridge DP (B Step)

1578

AR_HR_C0_4C_XHC

Alpine Ridge DP (C Step)

15D3

I doubt that customer plugged 3rtd party TBT device.