diff --git a/Source/Core/Core/HW/SI/SI_DeviceNull.h b/Source/Core/Core/HW/SI/SI_DeviceNull.h
@@ -15,7 +15,7 @@ class CSIDevice_Null final : public ISIDevice
 public:
   CSIDevice_Null(SIDevices device, int device_number);
 
-  int RunBuffer(u8* buffer, int length) override;
+  int RunBuffer(u8* buffer, int request_length) override;
   bool GetData(u32& hi, u32& low) override;
   void SendCommand(u32 command, u8 poll) override;
 };

diff --git a/Source/Core/Core/HW/VideoInterface.cpp b/Source/Core/Core/HW/VideoInterface.cpp
@@ -742,7 +742,7 @@ void Update(u64 ticks)
     if (Config::Get(Config::MAIN_REDUCE_POLLING_RATE))
       s_half_line_of_next_si_poll += GetHalfLinesPerEvenField() / 2;
     else
-      s_half_line_of_next_si_poll += SerialInterface::GetPollXLines();
+      s_half_line_of_next_si_poll += 2 * SerialInterface::GetPollXLines();
   }
   if (s_half_line_count == s_even_field_first_hl)
   {