diff --git a/src/engine/engine.h b/src/engine/engine.h
index 57696e94b..66d645291 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -56,8 +56,8 @@
 
 #define DIV_UNSTABLE
 
-#define DIV_VERSION "dev169"
-#define DIV_ENGINE_VERSION 169
+#define DIV_VERSION "dev170"
+#define DIV_ENGINE_VERSION 170
 // for imports
 #define DIV_VERSION_MOD 0xff01
 #define DIV_VERSION_FC 0xff02
diff --git a/src/engine/platform/sound/ymfm/ymfm_opm.cpp b/src/engine/platform/sound/ymfm/ymfm_opm.cpp
index 958dae579..9876c2bce 100644
--- a/src/engine/platform/sound/ymfm/ymfm_opm.cpp
+++ b/src/engine/platform/sound/ymfm/ymfm_opm.cpp
@@ -176,7 +176,7 @@ int32_t opm_registers::clock_noise_and_lfo()
 {
 	// base noise frequency is measured at 2x 1/2 FM frequency; this
 	// means each tick counts as two steps against the noise counter
-	uint32_t freq = noise_frequency();
+	uint32_t freq = noise_frequency() ^ 0x1f;
 	for (int rep = 0; rep < 2; rep++)
 	{
 		// evidence seems to suggest the LFSR is clocked continually and just
diff --git a/src/engine/platform/sound/ymfm/ymfm_opz.cpp b/src/engine/platform/sound/ymfm/ymfm_opz.cpp
index b20bea3c1..0bfce6bc6 100644
--- a/src/engine/platform/sound/ymfm/ymfm_opz.cpp
+++ b/src/engine/platform/sound/ymfm/ymfm_opz.cpp
@@ -327,7 +327,7 @@ int32_t opz_registers::clock_noise_and_lfo()
 {
 	// base noise frequency is measured at 2x 1/2 FM frequency; this
 	// means each tick counts as two steps against the noise counter
-	uint32_t freq = noise_frequency();
+	uint32_t freq = noise_frequency() ^ 0x1f;
 	for (int rep = 0; rep < 2; rep++)
 	{
 		// evidence seems to suggest the LFSR is clocked continually and just
diff --git a/src/gui/editControls.cpp b/src/gui/editControls.cpp
index f08893b96..2786e536e 100644
--- a/src/gui/editControls.cpp
+++ b/src/gui/editControls.cpp
@@ -509,9 +509,15 @@ void FurnaceGUI::drawMobileControls() {
           doAction(GUI_ACTION_SAVE_AS);
         }
 
-        ImGui::Button("1.1+ .dmf");
+        if (ImGui::Button("1.1+ .dmf")) {
+          mobileMenuOpen=false;
+          openFileDialog(GUI_FILE_SAVE_DMF);
+        }
         ImGui::SameLine();
-        ImGui::Button("Legacy .dmf");
+        if (ImGui::Button("Legacy .dmf")) {
+          mobileMenuOpen=false;
+          openFileDialog(GUI_FILE_SAVE_DMF_LEGACY);
+        }
         ImGui::SameLine();
         if (ImGui::Button("Export Audio")) {
           openFileDialog(GUI_FILE_EXPORT_AUDIO_ONE);