Command Buttons on Multiple Presentations Not Working

[Ian47]

I am running multiple presentation Slide Shows on screen at the same time,
however I have encountered a problem which I can't solve or understand why it
is occuring.

It is all to do with command buttons. Each presentation has one or many
command buttons, which all work as advertised when the presentations are run
individually.

However, as soon as they are run at the same time, i run into the problem.

Only the CommandButtons on the first presentation opened work. The rest do
nothing.

I am opening the presentations using code, and then arranging them in a kind
of 'Tiled' appearence

The code to open them is similar to below:

Set Pres1_ppt = New PowerPoint.Application
Pres1_ppt.Visible = True
fName = Directory & "\Presentation1.pps"
Pres1_ppt.Presentations.Open fName

Set Pres2_ppt = New PowerPoint.Application
Pres2_ppt.Visible = True
fName = Directory & "\Presentation2.pps"
Pres2_ppt.Presentations.Open fName

Set Pres3_ppt = New PowerPoint.Application
Pres3_ppt.Visible = True
fName = Directory & "\Presentation3.pps"
Pres3_ppt.Presentations.Open fName

Has anyone come accross this porblem before.

I suspect it might be in the way I am opening the presentation slide shows,
is there another way?

Thanks for you help

Ian