Post [Q] Trying to get into download mode, but it goes straight to fastboot

Hey all,
I recently got into a bit of strife with my G2 but eventually fixed that, and now Im trying to flash the stock firmware back on so I can go back to square one, but every time I try to get into download mode (power off, hold volume up, plug in usb) the small download mode box shows for less than a second, and it switches over to fastboot mode. Does anyone know how I can get it to stay in download mode?