Usercontrol not updating when placed on TabControl pages

[Enveetee]

Hi

Could someone shed some light on this please

VS2008 VB.NET

I have a usercontrol which has a number of labels on it. The usercontrol acts a bit like a listbox but I can control the background and foreground color of the labels it contains - nothing fancy use it for logging a process - a bit like a scrolling console window.

I have a form with 3 of these controls, Progress, Errors, and a debug logger. Works fine when placed on a form

...until I add a tab control with three paces and place each usercontrol on a tabpage. then random labels are not updated.

Move the UC off the tab control - fine
Move them on - random updates

What am I missing

Help please

Cheers