diff --git a/A2Mac/ViewController.swift b/A2Mac/ViewController.swift
index 6acb86c..ebd7213 100644
--- a/A2Mac/ViewController.swift
+++ b/A2Mac/ViewController.swift
@@ -710,7 +710,7 @@ class ViewController: NSViewController  {
 
     @IBAction func speedSelected(_ sender: NSButton) {
         if ( sender.title == "MAX" ) {
-            setCPUClockSpeed(freq: 1280)
+            setCPUClockSpeed(freq: 1600)
         }
         else if let freq = Double( sender.title ) {
             setCPUClockSpeed(freq: freq)
diff --git a/src/cpu/6502.c b/src/cpu/6502.c
index c496519..7596aa2 100644
--- a/src/cpu/6502.c
+++ b/src/cpu/6502.c
@@ -711,21 +711,18 @@ void softReset() {
 }
 
 void m6502_Run() {
-    static unsigned int clk = 0;
     
     // init time
 //#ifdef CLK_WAIT
 //    unsigned long long elpased = (unsigned long long)-1LL;
 //#endif
 
-    // we will also use this to pause the simulation if not finished by the end of the frame
-    clk_6502_per_frm_max = clk_6502_per_frm;
-    
 #ifdef SPEEDTEST
     for ( inst_cnt = 0; inst_cnt < iterations ; inst_cnt++ )
 #elif defined( CLK_WAIT )
         // we clear the clkfrm from ViewController Update()
-        for ( ; clkfrm < clk_6502_per_frm_max ; clkfrm += clk )
+        // we will also use this to pause the simulation if not finished by the end of the frame
+        for ( clk_6502_per_frm_max = clk_6502_per_frm; clkfrm < clk_6502_per_frm_max ; clkfrm += m6502_Step() )
 #else
     // this is for max speed only -- WARNING! It works only if simulation runs in a completely different thread from the Update()
     for ( ; ; )
@@ -763,10 +760,10 @@ void m6502_Run() {
         }
 #endif // INTERRUPT_CHECK_PER_STEP
         
-        m6502.clktime += ( clk = m6502_Step() );
-        printDisassembly( outdev );
     }
     
+    m6502.clktime += clk_6502_per_frm;
+    
     if( diskAccelerator_count ) {
         if( --diskAccelerator_count <= 0 ) {
             // make sure we only adjust clock once to get back to normal
diff --git a/src/dev/disk/woz.c b/src/dev/disk/woz.c
index df3fe9c..d037bad 100644
--- a/src/dev/disk/woz.c
+++ b/src/dev/disk/woz.c
@@ -251,11 +251,11 @@ uint8_t woz_read() {
 
     
 #else // WOZ_REAL_SPIN
-    clkelpased = m6502.clktime - m6502.clklast;
-    m6502.clklast = m6502.clktime;
+    clkelpased = m6502.clktime + clkfrm - m6502.clklast;
+    m6502.clklast = m6502.clktime + clkfrm;
     
     const int clkBeforeAdjusting = 250;
-    const int magicShiftOffset = 90;
+    const int magicShiftOffset = 80;
     
     uint16_t usedBytes = woz_trks[track].bytes_used < WOZ_TRACK_BYTE_COUNT ? woz_trks[track].bytes_used : WOZ_TRACK_BYTE_COUNT;
     if ( usedBytes ) {