Dell Dock WD19S Power issue

Hello, since a firmware update of my Dock (WD19S 180W), the power delivery is not constant when I run my GPU at full power, and cause very high and periodic fps drops (I seen it using MSI Afterburner). I can't run anything in 3D without getting FPS drops, it's really annoying. Even Minecraft gets FPS drops.

When powering my laptop (Vostro 7500) with the standard powering cable (130W), everything runs fine and the power is constant. It doesn't care of how many stuff is plugged in the Dock, and I can't use both the standard cable and the Dock (my pc seems to only use Dock powering in that case).

If anyone knows how to report this to the drivers/firmware developers, because it was working great before, and there is no way to downgrade.