diff --git a/src/Platform.h b/src/Platform.h
index 55a8e9cc..03233715 100644
--- a/src/Platform.h
+++ b/src/Platform.h
@@ -80,7 +80,6 @@ enum ConfigEntry
     Firm_Color,
     Firm_Message,
     Firm_MAC,
-    Firm_RandomizeMAC,
 
     AudioBitrate,
 };
diff --git a/src/SPI.cpp b/src/SPI.cpp
index 8d15656f..f586c2e5 100644
--- a/src/SPI.cpp
+++ b/src/SPI.cpp
@@ -406,6 +406,7 @@ void Reset()
 
         if (rep)
         {
+            mac[0] &= 0xFC; // ensure the MAC isn't a broadcast MAC
             memcpy(&Firmware[0x36], mac, 6);
 
             *(u16*)&Firmware[0x2A] = CRC16(&Firmware[0x2C], *(u16*)&Firmware[0x2C], 0x0000);
diff --git a/src/frontend/qt_sdl/Config.cpp b/src/frontend/qt_sdl/Config.cpp
index 7a0ec698..8072a6aa 100644
--- a/src/frontend/qt_sdl/Config.cpp
+++ b/src/frontend/qt_sdl/Config.cpp
@@ -106,7 +106,6 @@ int FirmwareBirthdayDay;
 int FirmwareFavouriteColour;
 std::string FirmwareMessage;
 std::string FirmwareMAC;
-bool RandomizeMAC;
 
 bool SocketBindAnyAddr;
 std::string LANDevice;
@@ -272,7 +271,6 @@ ConfigEntry ConfigFile[] =
     {"FirmwareFavouriteColour", 0, &FirmwareFavouriteColour, 0},
     {"FirmwareMessage", 2, &FirmwareMessage, (std::string)""},
     {"FirmwareMAC", 2, &FirmwareMAC, (std::string)""},
-    {"RandomizeMAC", 1, &RandomizeMAC, false},
 
     {"SockBindAnyAddr", 1, &SocketBindAnyAddr, false},
     {"LANDevice", 2, &LANDevice, (std::string)""},
diff --git a/src/frontend/qt_sdl/Config.h b/src/frontend/qt_sdl/Config.h
index f2f8ddcd..dc38982a 100644
--- a/src/frontend/qt_sdl/Config.h
+++ b/src/frontend/qt_sdl/Config.h
@@ -141,7 +141,6 @@ extern int FirmwareBirthdayDay;
 extern int FirmwareFavouriteColour;
 extern std::string FirmwareMessage;
 extern std::string FirmwareMAC;
-extern bool RandomizeMAC;
 
 extern bool SocketBindAnyAddr;
 extern std::string LANDevice;
diff --git a/src/frontend/qt_sdl/FirmwareSettingsDialog.cpp b/src/frontend/qt_sdl/FirmwareSettingsDialog.cpp
index 754cc8a5..69798d21 100644
--- a/src/frontend/qt_sdl/FirmwareSettingsDialog.cpp
+++ b/src/frontend/qt_sdl/FirmwareSettingsDialog.cpp
@@ -64,10 +64,8 @@ FirmwareSettingsDialog::FirmwareSettingsDialog(QWidget* parent) : QDialog(parent
     ui->overrideFirmwareBox->setChecked(Config::FirmwareOverrideSettings);
 
     ui->txtMAC->setText(QString::fromStdString(Config::FirmwareMAC));
-    ui->cbRandomizeMAC->setChecked(Config::RandomizeMAC);
 
     on_overrideFirmwareBox_toggled();
-    on_cbRandomizeMAC_toggled();
 }
 
 FirmwareSettingsDialog::~FirmwareSettingsDialog()
@@ -135,7 +133,6 @@ void FirmwareSettingsDialog::done(int r)
         std::string newMessage = ui->messageEdit->text().toStdString();
 
         std::string newMAC = ui->txtMAC->text().toStdString();
-        bool newRandomizeMAC = ui->cbRandomizeMAC->isChecked();
 
         if (   newOverride != Config::FirmwareOverrideSettings
             || newName != Config::FirmwareUsername
@@ -144,8 +141,7 @@ void FirmwareSettingsDialog::done(int r)
             || newBirthdayDay != Config::FirmwareBirthdayDay
             || newBirthdayMonth != Config::FirmwareBirthdayMonth
             || newMessage != Config::FirmwareMessage
-            || newMAC != Config::FirmwareMAC
-            || newRandomizeMAC != Config::RandomizeMAC)
+            || newMAC != Config::FirmwareMAC)
         {
             if (RunningSomething
                 && QMessageBox::warning(this, "Reset necessary to apply changes",
@@ -163,7 +159,6 @@ void FirmwareSettingsDialog::done(int r)
             Config::FirmwareMessage = newMessage;
 
             Config::FirmwareMAC = newMAC;
-            Config::RandomizeMAC = newRandomizeMAC;
 
             Config::Save();
 
@@ -210,9 +205,3 @@ void FirmwareSettingsDialog::on_overrideFirmwareBox_toggled()
     ui->grpUserSettings->setDisabled(disable);
     ui->grpWifiSettings->setDisabled(disable);
 }
-
-void FirmwareSettingsDialog::on_cbRandomizeMAC_toggled()
-{
-    bool disable = ui->cbRandomizeMAC->isChecked();
-    ui->txtMAC->setDisabled(disable);
-}
diff --git a/src/frontend/qt_sdl/FirmwareSettingsDialog.h b/src/frontend/qt_sdl/FirmwareSettingsDialog.h
index 97bf5c07..b3695e2f 100644
--- a/src/frontend/qt_sdl/FirmwareSettingsDialog.h
+++ b/src/frontend/qt_sdl/FirmwareSettingsDialog.h
@@ -124,7 +124,6 @@ private slots:
 
     void on_cbxBirthdayMonth_currentIndexChanged(int idx);
     void on_overrideFirmwareBox_toggled();
-    void on_cbRandomizeMAC_toggled();
 
 private:
     bool verifyMAC();
diff --git a/src/frontend/qt_sdl/FirmwareSettingsDialog.ui b/src/frontend/qt_sdl/FirmwareSettingsDialog.ui
index a97689cf..245e6418 100644
--- a/src/frontend/qt_sdl/FirmwareSettingsDialog.ui
+++ b/src/frontend/qt_sdl/FirmwareSettingsDialog.ui
@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>511</width>
-    <height>342</height>
+    <height>338</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -144,9 +144,9 @@
        </widget>
       </item>
       <item row="1" column="1">
-       <widget class="QCheckBox" name="cbRandomizeMAC">
+       <widget class="QLabel" name="label_6">
         <property name="text">
-         <string>Randomize</string>
+         <string>(leave empty to use default MAC)</string>
         </property>
        </widget>
       </item>
diff --git a/src/frontend/qt_sdl/Platform.cpp b/src/frontend/qt_sdl/Platform.cpp
index 8f2163ec..dd2a5d7b 100644
--- a/src/frontend/qt_sdl/Platform.cpp
+++ b/src/frontend/qt_sdl/Platform.cpp
@@ -57,11 +57,11 @@ void IPCInit()
     if (!IPCBuffer->attach())
     {
         printf("IPC sharedmem doesn't exist. creating\n");
-        if (!IPCBuffer->create(4096))
+        if (!IPCBuffer->create(1024))
         {
             printf("IPC sharedmem create failed :(\n");
             delete IPCBuffer;
-            IPCBuffer= nullptr;
+            IPCBuffer = nullptr;
             return;
         }
 
@@ -89,7 +89,17 @@ void IPCInit()
 
 void IPCDeInit()
 {
-    if (IPCBuffer) delete IPCBuffer;
+    if (IPCBuffer)
+    {
+        IPCBuffer->lock();
+        u8* data = (u8*)IPCBuffer->data();
+        *(u16*)&data[0] &= ~(1<<IPCInstanceID);
+        IPCBuffer->unlock();
+
+        IPCBuffer->detach();
+        delete IPCBuffer;
+    }
+
     IPCBuffer = nullptr;
 }
 
@@ -195,7 +205,6 @@ bool GetConfigBool(ConfigEntry entry)
     case DSiSD_ReadOnly: return Config::DSiSDReadOnly != 0;
     case DSiSD_FolderSync: return Config::DSiSDFolderSync != 0;
 
-    case Firm_RandomizeMAC: return Config::RandomizeMAC != 0;
     case Firm_OverrideSettings: return Config::FirmwareOverrideSettings != 0;
     }