diff --git a/src/game/gameport.c b/src/game/gameport.c
index 67447d447..5bbfe8aac 100644
--- a/src/game/gameport.c
+++ b/src/game/gameport.c
@@ -306,6 +306,9 @@ gameport_remap(void *priv, uint16_t address)
     gameport_t *dev = (gameport_t *) priv;
     gameport_t *other_dev;
 
+    if (dev == NULL)
+        return;
+
     if (dev->addr) {
         /* Remove this port from the active ports list. */
         if (active_gameports == dev) {
diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index cb2ede45a..4c73abf21 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -1152,8 +1152,9 @@ sb_ct1745_mixer_write(uint16_t addr, uint8_t val, void *priv)
                         else if ((val & 0x06) == 0x02)
                             mpu401_change_addr(sb->mpu, 0);
                     }
+
+                    sb->gameport_addr = 0;
                     if (sb->gameport != NULL) {
-                        sb->gameport_addr = 0;
                         gameport_remap(sb->gameport, 0);
                         if (!(val & 0x01)) {
                             sb->gameport_addr = 0x200;
@@ -1373,7 +1374,7 @@ sb_ct1745_mixer_read(uint16_t addr, void *priv)
                     else
                         ret = 0x06; /* Should never happen. */
                 }
-                if (!sb->gameport_addr && (sb->gameport != NULL))
+                if (!sb->gameport_addr)
                     ret |= 0x01;
                 break;