This question has been asked a couple of times, with some interresting answers but I need to go further in depth. My device is a Corsair Void Pro USB. I want to change its USB A connector to a USB C connector, and it must work on all my devices (PC and mobile). The reason for this conversion is that USB A is bulky, so is the USB A to USB C adaptor, and most of my devices have USB C receptacles. Those that don't, I'll just use a minuscule converter (shown below).
I used this specific connector:
I followed this popular Youtube video (and adapted it for my specific connector) and it worked on my Google Pixel Slate. But when using an adapter to convert USB C back to USB A (for my PC), the device worked when the USB C connector was inserted in one way but not the other (i.e. it's not reversible). Here's the adapor:
WARNING: Any adaptor with a USB-C receptacle such as this one is potentially unsafe according to the USB spec. See MacGuffin's anwser.
So I figured I had to wire both the A and the B side of the USB C connector (that required some micro-soldering directly on the connector leads). Now the connector works when inserted both ways in the adaptor. Here's the schematic:
The device works fine on my Pixel Slate, on a Chromebook and on my PC. But not on my phone (Google Pixel 3), no matter the way it's connected! It kind of starts for 2 or 3 seconds on a Google Pixel 1 but then it stops. However, here's a silly cascade of adaptors that just works:
USB C connector -> USB C female to USB A male -> USB A female to USB C male -> Phone
The white adaptor is the one that came with a Google Titan security key set.
Now the question: what's missing from my connector so my device works on my phone? (Or what's so special about Google's USB A to USB C adaptor?)