diff --git a/source/cd_hw/cdd.c b/source/cd_hw/cdd.c
index 61ef52d..ef0f9e4 100644
--- a/source/cd_hw/cdd.c
+++ b/source/cd_hw/cdd.c
@@ -920,6 +920,9 @@ void cdd_update(void)
     }
     else if (cdd.toc.tracks[cdd.index].fd)
     {
+      /* AUDIO track playing */
+      scd.regs[0x36>>1].byte.h = 0x00;
+
       if (cdd.lba < cdd.toc.tracks[cdd.index].start)
       {
         fseek(cdd.toc.tracks[cdd.index].fd, (cdd.toc.tracks[cdd.index].start * 2352) - cdd.toc.tracks[cdd.index].offset, SEEK_SET);
@@ -961,38 +964,37 @@ void cdd_process(void)
     case 0x02:  /* Read TOC */
     {
       /* Infos automatically retrieved by CDD processor from Q-Channel */
-      /* commands 0x00-0x02: from current block Q-Channel data field  */
-      /* commands 0x03-0x05: from Lead-In area Q-Channel data field  */
+      /* commands 0x00-0x02 (current block) and 0x03-0x05 (Lead-In) */
       switch (scd.regs[0x44>>1].byte.l)
       {
-        case 0x00:  /* Absolute position (MM:SS:FF) */
+        case 0x00:  /* Current Absolute Time (MM:SS:FF) */
         {
           int lba = cdd.lba + 150;
           scd.regs[0x38>>1].w = cdd.status << 8;
           scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
           scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
           scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
-          scd.regs[0x40>>1].byte.h = 0x00;   /* TODO: check what is returned in RS8 (note: bit 1 is checked by BIOS) */
+          scd.regs[0x40>>1].byte.h = cdd.index ? 0x01 : 0x04; /* Current block flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
           break;
         }
 
-        case 0x01:  /* Track relative position (MM:SS:FF) */
+        case 0x01:  /* Current Track Relative Time (MM:SS:FF) */
         {
           int lba = cdd.lba - cdd.toc.tracks[cdd.index].start;
           scd.regs[0x38>>1].w = (cdd.status << 8) | 0x01;
           scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
           scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
           scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
-          scd.regs[0x40>>1].byte.h = 0x00;   /* TODO: check what is returned in RS8 */
+          scd.regs[0x40>>1].byte.h = cdd.index ? 0x00 : 0x04; /* Current block flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
           break;
         }
 
-        case 0x02:  /* Current track */
+        case 0x02:  /* Current Track Number */
         {
           scd.regs[0x38>>1].w = (cdd.status << 8) | 0x02;
           scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[cdd.index + 1] : 0x0A0A;
           scd.regs[0x3c>>1].w = 0x0000;
-          scd.regs[0x3e>>1].w = 0x0000;   /* TODO: check what is returned in RS6 */
+          scd.regs[0x3e>>1].w = 0x0000; /* Disk Control Code (?) in RS6 */
           scd.regs[0x40>>1].byte.h = 0x00;
           break;
         }
@@ -1008,17 +1010,17 @@ void cdd_process(void)
           break;
         }
 
-        case 0x04:  /* Number of tracks */
+        case 0x04:  /* First & Last Track Numbers */
         {
           scd.regs[0x38>>1].w = (cdd.status << 8) | 0x04;
           scd.regs[0x3a>>1].w = 0x0001;
           scd.regs[0x3c>>1].w = lut_BCD_16[cdd.toc.last];
-          scd.regs[0x3e>>1].w = 0x0000;   /* TODO: check what is returned in RS6-RS7 */
-          scd.regs[0x40>>1].byte.h = 0x00;   /* TODO: check what is returned in RS8 */
+          scd.regs[0x3e>>1].w = 0x0000; /* Drive Version (?) in RS6-RS7 */
+          scd.regs[0x40>>1].byte.h = 0x00;  /* Lead-In flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
           break;
         }
 
-        case 0x05:  /* Track start (MM:SS:FF) */
+        case 0x05:  /* Track Start Time (MM:SS:FF) */
         {
           int track = scd.regs[0x46>>1].byte.h * 10 + scd.regs[0x46>>1].byte.l;
           int lba = cdd.toc.tracks[track-1].start + 150;
@@ -1026,10 +1028,10 @@ void cdd_process(void)
           scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
           scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
           scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
-          scd.regs[0x40>>1].byte.h = track % 10;
+          scd.regs[0x40>>1].byte.h = track % 10;  /* Track Number (low digit) */
           if (track == 1)
           {
-            /* RS6 bit 3 is set for DATA track */
+            /* RS6 bit 3 is set for the first (DATA) track */
             scd.regs[0x3e>>1].byte.h |= 0x08;
           }
           break;
diff --git a/source/cd_hw/cdd.h b/source/cd_hw/cdd.h
index c0e0710..c2d7d27 100644
--- a/source/cd_hw/cdd.h
+++ b/source/cd_hw/cdd.h
@@ -53,7 +53,7 @@
 #define CD_END   0x0C
 
 /* CD blocks scanning speed */
-#define CD_SCAN_SPEED 10
+#define CD_SCAN_SPEED 30
 
 #define CD_MAX_TRACKS 100