diff --git a/libsrc/geos/mousesprite/mouse.s b/libsrc/geos/mousesprite/mouse.s
index 8e49af16c..a5f59fa2e 100644
--- a/libsrc/geos/mousesprite/mouse.s
+++ b/libsrc/geos/mousesprite/mouse.s
@@ -110,7 +110,8 @@ _mouse_pos:
 
 	ldy	#0			; Structure offset
 
-	sei				; Disable interrupts
+        php
+        sei				; Disable interrupts
 
        	lda     mouseXPos		; Transfer the position
 	sta	(ptr1),y
@@ -124,7 +125,7 @@ _mouse_pos:
 	iny
 	sta	(ptr1),y
 
-	cli				; Reenable interrupts
+	plp				; Reenable interrupts
 	rts				; Done
 
 ; --------------------------------------------------------------------------
@@ -157,13 +158,14 @@ _mouse_info:
 
 _mouse_move:
 	jsr	popsreg			; Get X
-	sei				; Disable interrupts
+        php
+        sei				; Disable interrupts
 	sta	mouseYPos
 	lda	sreg
 	ldx	sreg+1
    	sta	mouseXPos
 	stx	mouseXPos+1
-	cli		   		; Enable interrupts
+	plp		   		; Enable interrupts
 	rts
 
 ; --------------------------------------------------------------------------
diff --git a/libsrc/geos/system/get_ostype.s b/libsrc/geos/system/get_ostype.s
index bd40b5bf6..f92f634a9 100644
--- a/libsrc/geos/system/get_ostype.s
+++ b/libsrc/geos/system/get_ostype.s
@@ -35,7 +35,9 @@ get_tv:
 	    bne tvmode
 only40:	    ldx #0			; COLUMNS40
 tvmode:					; PAL/NTSC check here, result in A
-	    bit rasreg
+            php
+	    sei                         ; disable interrupts
+            bit rasreg
 	    bpl tvmode			; wait for rasterline  127<x<256
 	    lda #24			; (rasterline now >=256!)
 modelp:	    cmp rasreg			; wait for rasterline = 24 (or 280 on PAL)
@@ -48,4 +50,5 @@ ntsc:	    lda #$80			; NTSC
 
 modeend:    stx tmp1
 	    ora tmp1
+	    plp                         ; restore interrupt state
 	    rts