Again about jerky mouse

Everything is fine if I run the code below as it is. But I get a jerky mouse if I comment out the text line. Why? What is the proper way to solve this problem?

	Win = CreateWindow("Test",100,100,400,400,0)
	Can = CreateCanvas(0,0,400,400, Win)
	SetBuffer(CanvasBuffer(Can))
	
	Repeat
	
		Cls
		
		If KeyDown(1) Then
			End
		EndIf		
		
		Text 0,0, "hi there"

		FlipCanvas(can,True)
		
	Forever

	End