diff --git a/sound/ppc/daca.c b/sound/ppc/daca.c
index c5a1f0b..0c81457 100644
--- a/sound/ppc/daca.c
+++ b/sound/ppc/daca.c
@@ -115,7 +115,7 @@
 		return -ENODEV;
 	change = mix->deemphasis != ucontrol->value.integer.value[0];
 	if (change) {
-		mix->deemphasis = ucontrol->value.integer.value[0];
+		mix->deemphasis = !!ucontrol->value.integer.value[0];
 		daca_set_volume(mix);
 	}
 	return change;
@@ -149,15 +149,20 @@
 {
 	struct snd_pmac *chip = snd_kcontrol_chip(kcontrol);
 	struct pmac_daca *mix;
+	unsigned int vol[2];
 	int change;
 
 	if (! (mix = chip->mixer_data))
 		return -ENODEV;
-	change = mix->left_vol != ucontrol->value.integer.value[0] ||
-		mix->right_vol != ucontrol->value.integer.value[1];
+	vol[0] = ucontrol->value.integer.value[0];
+	vol[1] = ucontrol->value.integer.value[1];
+	if (vol[0] > DACA_VOL_MAX || vol[1] > DACA_VOL_MAX)
+		return -EINVAL;
+	change = mix->left_vol != vol[0] ||
+		mix->right_vol != vol[1];
 	if (change) {
-		mix->left_vol = ucontrol->value.integer.value[0];
-		mix->right_vol = ucontrol->value.integer.value[1];
+		mix->left_vol = vol[0];
+		mix->right_vol = vol[1];
 		daca_set_volume(mix);
 	}
 	return change;
@@ -188,7 +193,7 @@
 		return -ENODEV;
 	change = mix->amp_on != ucontrol->value.integer.value[0];
 	if (change) {
-		mix->amp_on = ucontrol->value.integer.value[0];
+		mix->amp_on = !!ucontrol->value.integer.value[0];
 		i2c_smbus_write_byte_data(mix->i2c.client, DACA_REG_GCFG,
 					  mix->amp_on ? 0x05 : 0x04);
 	}