Default Headphone jacks?

So I just have a question does anyone know why some devices don't recognize the L shaped headphone Jack? I recently got the G pad 7.0 and it doesn't recognize it at all the headphones work with the G3 perfectly and when I plug in headphones that have a straight headphone Jack it recognizes them. This has happened before with another phone I had but I'm just wondering if anyone knows why this happens? Or if there's a fix? Please and thank you.