diff --git a/usr.sbin/mixer/mixer.c b/usr.sbin/mixer/mixer.c
--- a/usr.sbin/mixer/mixer.c
+++ b/usr.sbin/mixer/mixer.c
@@ -426,11 +426,14 @@
 	m = d->parent_mixer;
 	cp = mixer_get_ctl(m->dev, C_MUT);
 	val = p;
-	if (strncmp(val, "off", strlen(val)) == 0 || *val == '0')
+	if (strncmp(val, "off", strlen(val)) == 0 ||
+	    strncmp(val, "0", strlen(val)) == 0)
 		opt = MIX_UNMUTE;
-	else if (strncmp(val, "on", strlen(val)) == 0 || *val == '1')
+	else if (strncmp(val, "on", strlen(val)) == 0 ||
+	    strncmp(val, "1", strlen(val)) == 0)
 		opt = MIX_MUTE;
-	else if (strncmp(val, "toggle", strlen(val)) == 0 || *val == '^')
+	else if (strncmp(val, "toggle", strlen(val)) == 0 ||
+	    strncmp(val, "^", strlen(val)) == 0)
 		opt = MIX_TOGGLEMUTE;
 	else {
 		warnx("%s: no such modifier", val);
@@ -459,13 +462,17 @@
 	m = d->parent_mixer;
 	cp = mixer_get_ctl(m->dev, C_SRC);
 	val = p;
-	if (strncmp(val, "add", strlen(val)) == 0 || *val == '+')
+	if (strncmp(val, "add", strlen(val)) == 0 ||
+	    strncmp(val, "+", strlen(val)) == 0)
 		opt = MIX_ADDRECSRC;
-	else if (strncmp(val, "remove", strlen(val)) == 0 || *val == '-')
+	else if (strncmp(val, "remove", strlen(val)) == 0 ||
+	    strncmp(val, "-", strlen(val)) == 0)
 		opt = MIX_REMOVERECSRC;
-	else if (strncmp(val, "set", strlen(val)) == 0 || *val == '=')
+	else if (strncmp(val, "set", strlen(val)) == 0 ||
+	    strncmp(val, "=", strlen(val)) == 0)
 		opt = MIX_SETRECSRC;
-	else if (strncmp(val, "toggle", strlen(val)) == 0 || *val == '^')
+	else if (strncmp(val, "toggle", strlen(val)) == 0 ||
+	    strncmp(val, "^", strlen(val)) == 0)
 		opt = MIX_TOGGLERECSRC;
 	else {
 		warnx("%s: no such modifier", val);