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HidD_GetManufacturerString and similar functions return success, but do not modify the buffer

I am having an issue with 3 functions ( HidD_GetManufacturerString , HidD_GetProductString , HidD_GetSerialNumberString ). The issue is that they return TRUE (indicating success), but do not modify the buffer (not even adding a terminator).

MSDN pages for the functions:

HidD_GetManufacturerString : https://msdn.microsoft.com/en-us/library/windows/hardware/ff538959%28v=vs.85%29.aspx

HidD_GetProductString : https://msdn.microsoft.com/en-us/library/windows/hardware/ff539681%28v=vs.85%29.aspx

HidD_GetSerialNumberString : https://msdn.microsoft.com/en-us/library/windows/hardware/ff539683%28v=vs.85%29.aspx

Here is the code that actually calls the methods:

wchar_t manufacturer[MAX_SERIAL_LEN];
wchar_t product[MAX_SERIAL_LEN];
wchar_t serial[MAX_SERIAL_LEN];
ZeroMemory(manufacturer, MAX_SERIAL_LEN);
ZeroMemory(product, MAX_SERIAL_LEN);
ZeroMemory(serial, MAX_SERIAL_LEN);
HidD_GetManufacturerString(hFile, manufacturer, MAX_SERIAL_LEN);
HidD_GetProductString(hFile, product, MAX_SERIAL_LEN);
HidD_GetSerialNumberString(hFile, serial, MAX_SERIAL_LEN);
printf("Information for device %s\nManufacturer: %S\nProduct: %S\nSerial: %S\n\n", 
    DevIntfDetailData->DevicePath, 
    manufacturer, product, serial
hFile is opened like this:
HANDLE hFile = CreateFile(DevIntfDetailData->DevicePath, 0, FILE_SHARE_READ, 0, OPEN_EXISTING, 0, 0);
DevIntfDetailData is filled using SetupDiGetDeviceInterfaceDetail
MAX_SERIAL_LEN is defined as
sizeof(wchar_t)*127
                Erm, how could you know that it isn't just an empty string when you use ZeroMemory?  Delete those calls and try again.
– Hans Passant
                Mar 23, 2016 at 21:26
                Like I said in the first paragraph, it doesn't even add a terminator, which it would on a zero character string. The buffer really isn't being touched
– rscarson
                Mar 23, 2016 at 21:44
                Maybe you missed the point.  How do you detect it writing a zero character when the buffer already contains zeros?
– Hans Passant
                Mar 23, 2016 at 21:48
Probably a driver bug.
I have a similar problem: The functions return TRUE, but the buffer is either not touched at all or it is filled with random garbage.
Here’s the catch: This happens only for my headset, and only while I am actively using its microphone via Skype/Teams/etc. Once I leave a call, the functions start returning ordinary names again.
This leads me to believe you’re seeing a faulty driver. Mine is the Windows standard headset driver on Windows 10 1907.
        
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