Parallax Effect, background not visible

Because your SoundPan commands are within the bounds of your If KeyHit(205) command.

Try indenting your code. It helps A LOT to uncover mistakes like this.

Heres what you've got (indented):

If KeyDown (203) ;Set the plane to rotate left if the user chooses left
	; Decrease the frame by 1 respectively
	frame = frame - 1

	; Play the plane sound out of the left speaker
	pan# = -1.000
	
	; If the frame is below the minimum level, reset it to the maximum value of the array
	If frame <= 0
		frame = rotations - 1
	EndIf
ElseIf KeyDown (205) ; Set the plane to rotate right if the user chooses right

	; Increase the frame by 1 respectively
	frame = frame + 1

	; Play the plane sound of of the right speaker
	pan# = 1.000
	
	; If the frame goes above the maximum level, reset the plane to the first frame
	If frame >= rotations
		frame = 0 
	EndIf

	SoundPan planesound, pan#
	SoundPan propsound, pan#
EndIf

and heres what you should have (indented):

If KeyDown (203) Set the plane to rotate left if the user chooses left

	; Decrease the frame by 1 respectively
	frame = frame - 1

	; Play the plane sound out of the left speaker
	pan# = -1.000
	
	; If the frame is below the minimum level, reset it to the maximum value of the array
	If frame <= 0
		frame = rotations - 1
	EndIf
ElseIf KeyDown (205); Set the plane to rotate right if the user chooses right

	; Increase the frame by 1 respectively
	frame = frame + 1

	; Play the plane sound of of the right speaker
	pan# = 1.000
	
	; If the frame goes above the maximum level, reset the plane to the first frame
	If frame >= rotations
		frame = 0 
	EndIf
EndIf

SoundPan planesound, pan#
SoundPan propsound, pan#

For some tips, check out my programming tutorial website.

Heres some indenting tipe on the site:
http://home.cmit.net/rwolbeck/programmingtutorial/reference/goodhabits.htm#indentation


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