diff --git a/sys/powerpc/powermac/macio.c b/sys/powerpc/powermac/macio.c
index dad261cbbb32..6a0b9136fc8f 100644
--- a/sys/powerpc/powermac/macio.c
+++ b/sys/powerpc/powermac/macio.c
@@ -236,13 +236,45 @@ macio_add_intr(phandle_t devnode, struct macio_devinfo *dinfo)
 static void
 macio_add_reg(phandle_t devnode, struct macio_devinfo *dinfo)
 {
-	struct	macio_reg *reg;
-	int	i, nreg;
+	struct		macio_reg *reg, *regp;
+	phandle_t 	child;
+	char		buf[8];
+	int		i, layout_id = 0, nreg, res;
 
 	nreg = OF_getprop_alloc(devnode, "reg", sizeof(*reg), (void **)&reg);
 	if (nreg == -1)
 		return;
 
+        /*
+         *  Some G5's have broken properties in the i2s-a area. If so we try
+         *  to fix it. Right now we know of two different cases, one for
+         *  sound layout-id 36 and the other one for sound layout-id 76.
+         *  What is missing is the base address for the memory addresses.
+         *  We take them from the parent node (i2s) and use the size
+         *  information from the child. 
+         */
+
+        if (reg[0].mr_base == 0) {
+		child = OF_child(devnode);
+		while (child != 0) {
+			res = OF_getprop(child, "name", buf, sizeof(buf));
+			if (res > 0 && strcmp(buf, "sound") == 0)
+				break;
+			child = OF_peer(child);
+		}
+
+                res = OF_getprop(child, "layout-id", &layout_id,
+				sizeof(layout_id));
+
+                if (res > 0 && (layout_id == 36 || layout_id == 76)) {
+                        res = OF_getprop_alloc(OF_parent(devnode), "reg",
+						sizeof(*regp), (void **)&regp);
+                        reg[0] = regp[0];
+                        reg[1].mr_base = regp[1].mr_base;
+                        reg[2].mr_base = regp[1].mr_base + reg[1].mr_size;
+                }
+        } 
+
 	for (i = 0; i < nreg; i++) {
 		resource_list_add(&dinfo->mdi_resources, SYS_RES_MEMORY, i,
 		    reg[i].mr_base, reg[i].mr_base + reg[i].mr_size,
@@ -284,6 +316,7 @@ macio_attach(device_t dev)
 	phandle_t  subchild;
         device_t cdev;
         u_int reg[3];
+	char compat[32];
 	int error, quirks;
 
 	sc = device_get_softc(dev);
@@ -297,6 +330,9 @@ macio_attach(device_t dev)
 		return (ENXIO);
 	}
 
+	/* Used later to see if we have to enable the I2S part. */
+	OF_getprop(root, "compatible", compat, sizeof(compat));
+
 	sc->sc_base = reg[2];
 	sc->sc_size = MACIO_REG_SIZE;
 
@@ -378,6 +414,21 @@ macio_attach(device_t dev)
 			
 			bus_write_4(sc->sc_memr, HEATHROW_FCR, fcr);
 		}
+
+		/*
+		 * Make sure the I2S0 and the I2S0_CLK are enabled.
+		 * On certain G5's they are not.
+		 */
+		if ((strcmp(ofw_bus_get_name(cdev), "i2s") == 0) &&
+		    (strcmp(compat, "K2-Keylargo") == 0)) {
+
+			uint32_t fcr1;
+
+			fcr1 = bus_read_4(sc->sc_memr, KEYLARGO_FCR1);
+			fcr1 |= FCR1_I2S0_CLK_ENABLE | FCR1_I2S0_ENABLE;
+			bus_write_4(sc->sc_memr, KEYLARGO_FCR1, fcr1);
+		}
+
 	}
 
 	return (bus_generic_attach(dev));
diff --git a/sys/powerpc/powermac/maciovar.h b/sys/powerpc/powermac/maciovar.h
index 61fac469b37f..ed9c15d092d7 100644
--- a/sys/powerpc/powermac/maciovar.h
+++ b/sys/powerpc/powermac/maciovar.h
@@ -48,6 +48,9 @@
 #define FCR_ENET_ENABLE	0x60000000
 #define FCR_ENET_RESET	0x80000000
 
+#define FCR1_I2S0_CLK_ENABLE	0x00001000
+#define FCR1_I2S0_ENABLE	0x00002000
+
 /* Used only by macio_enable_wireless() for now. */
 #define KEYLARGO_GPIO_BASE	0x6a
 #define KEYLARGO_EXTINT_GPIO_REG_BASE	0x58