Vertex VX-427 problem

I got a used VX-427 I want to use at work with their system. I’ve seemed to figure out most of their system as in the frequency, modulation mode 11K0F3E (which I figure is determined by power setting, the other my radio uses is 16K0F3E), etc. I also got the programming cable and software for it. But I just figured out another issue the radio has and am not sure if it’s some setting I can’t find. I also have a BaoFeng I can use to listen to it and realized that when I first key the VX I hear a carrier and when I try to talk it sounds muffled almost like distortion or something solid over the mic but discovered if I keep it keyed up, after 5 seconds it sounds like the mic turns on and I can hear fairly normal.
Does anyone have any idea why it might do that? Could it be a setting or is something wrong with the unit?