diff --git a/Machines/Commodore/1540/C1540.cpp b/Machines/Commodore/1540/C1540.cpp
index ed5814ff5..ef207a8ff 100644
--- a/Machines/Commodore/1540/C1540.cpp
+++ b/Machines/Commodore/1540/C1540.cpp
@@ -126,7 +126,6 @@ void Machine::process_input_bit(int value, unsigned int cycles_since_index_hole)
 	{
 		_driveVIA.set_sync_detected(true);
 		_bit_window_offset = -1; // i.e. this bit isn't the first within a data window, but the next might be
-		printf("X");
 	}
 	else
 	{
@@ -141,7 +140,6 @@ void Machine::process_input_bit(int value, unsigned int cycles_since_index_hole)
 		{
 			set_overflow_line(true);
 		}
-		printf("%02x.", (uint8_t)_shift_register);
 	}
 	else
 		set_overflow_line(false);
diff --git a/Storage/Disk/Formats/D64.cpp b/Storage/Disk/Formats/D64.cpp
index bb7bde5ae..38765eb50 100644
--- a/Storage/Disk/Formats/D64.cpp
+++ b/Storage/Disk/Formats/D64.cpp
@@ -112,8 +112,8 @@ std::shared_ptr<Track> D64::get_track_at_position(unsigned int position)
 		uint8_t *sector_data = &data[sector * 349];
 		sector_data[0] = sector_data[1] = sector_data[2] = 0xff;
 
-		uint8_t sector_number = (uint8_t)(sector+1);
-		uint8_t track_number = (uint8_t)((position >> 1) + 1);
+		uint8_t sector_number = (uint8_t)(sector);				// sectors count from 0
+		uint8_t track_number = (uint8_t)((position >> 1) + 1);	// tracks count from 1
 		uint8_t checksum = (uint8_t)(sector_number ^ track_number ^ _disk_id ^ (_disk_id >> 8));
 		uint8_t header_start[4] = {
 			0x08, checksum, sector_number, track_number