Tab page loads slow due to background image and transparent controls

Question

Hi All, I have been struggling with this problem since weeks and still havent found the solution to this. I am using .Net 1.1. I have a form with a tabcontrol in it. I have defined a background image for each of the 7 tab pages in the tabcontrol. I have some 10 to 15 controls in each of the tab page. When i try to run the program and navigate through each tab, it loads very slowly. I determined with some tests that this problem occurs only when the background color of controls like "GroupBox", "Panel" and "labels" is transparent. If I dont have an background image then the loading is fast. And if I do have an image and the controls have any backcolor, its still ok. The problem comes in only when I have an image and the backcolor of controls is set to Transparent. Can anybody please help me with this as this seems to be a major block in my presentation of the form. Thanks in advance,