Stock Headunit

[TWINN]

What's up guys,

I just got a 92 ES300 for a real good deal. 108K miles on it. The only problem is is that when I got it. The stock stereo took around 1/2 and hour to turn up and when it was up, it wouldn't come back down. The volume button was broke too. The guy I bought it from had another Lexus for parts and he exchanged the stereo. This one I think is worse! He installed it and now, the screen flashes on and off and at the same time you hear a buzzing sound coming from the antenna as if its trying to come out but the unit shuts on and off so it can't decide. Can anyone help me.

Thanks,

TWINN