diff --git a/doc/notes.txt b/doc/notes.txt
index c6369f24..a56e4484 100644
--- a/doc/notes.txt
+++ b/doc/notes.txt
@@ -51,10 +51,7 @@ TODO:
 - tools (memory, disasm) use debugging state
 - text log debugging script
 - NES crt should mark raster pos when debugging
-- make sure we don't store files in local storage unnecc.
-- state buffer/replay
 - intro/help text for each platform
-- make sure controls work with replay feature (we'll have to save control state every frame)
 - vscode/atom extension?
 - navigator.getGamepads
 
diff --git a/src/recorder.ts b/src/recorder.ts
index 84a63c7d..9925e1fb 100644
--- a/src/recorder.ts
+++ b/src/recorder.ts
@@ -24,7 +24,8 @@ export class StateRecorderImpl implements EmuRecorder {
         this.checkpoints = [];
         this.framerecs = [];
         this.frameCount = 0;
-        this.lastSeekFrame = -1;
+        this.lastSeekFrame = 0;
+        if (this.callbackStateChanged) this.callbackStateChanged();
     }
 
     frameRequested() : boolean {
@@ -32,32 +33,35 @@ export class StateRecorderImpl implements EmuRecorder {
         if (this.checkpoints.length >= this.maxCheckpoints) {
             return false;
         }
-        // record the control state, if available
-        if (this.platform.saveControlsState) {
-            this.framerecs.push({
-                controls:this.platform.saveControlsState(),
-                seed:getNoiseSeed()
-            });
+        var controls = {
+          controls:this.platform.saveControlsState(),
+          seed:getNoiseSeed()
+        };
+        var requested = false;
+        // are we replaying? then we don't need to save a frame, just replace controls
+        if (this.lastSeekFrame < this.frameCount) {
+            this.loadControls(this.lastSeekFrame);
+        } else {
+            // record the control state, if available
+            if (this.platform.saveControlsState) {
+                this.framerecs.push(controls);
+            }
+            // time to save next frame?
+            requested = (this.frameCount++ % this.checkpointInterval) == 0;
         }
-        // pick up where we left off, if we used the seek function
-        if (this.lastSeekFrame >= 0) {
-            this.frameCount = this.lastSeekFrame;
-            this.lastSeekFrame = -1;
-            // truncate buffers
-            this.checkpoints = this.checkpoints.slice(0, Math.floor((this.frameCount + this.checkpointInterval - 1) / this.checkpointInterval));
-            this.framerecs = this.framerecs.slice(0, this.frameCount);
-        }
-        // time to save next frame?
-        if (this.callbackStateChanged) {
-            this.callbackStateChanged();
-        }
-        return (this.frameCount++ % this.checkpointInterval) == 0;
+        this.lastSeekFrame++;
+        if (this.callbackStateChanged) this.callbackStateChanged();
+        return requested;
     }
     
     numFrames() : number {
         return this.frameCount;
     }
     
+    currentFrame() : number {
+        return this.lastSeekFrame;
+    }
+    
     recordFrame(state : EmuState) {
         this.checkpoints.push(state);
     }
@@ -79,8 +83,7 @@ export class StateRecorderImpl implements EmuRecorder {
             this.platform.loadState(state);
             while (frame < seekframe) {
                 if (frame < this.framerecs.length) {
-                    this.platform.loadControlsState(this.framerecs[frame].controls);
-                    setNoiseSeed(this.framerecs[frame].seed);
+                    this.loadControls(frame);
                 }
                 frame++;
                 this.platform.advance(frame < seekframe); // TODO: infinite loop?
@@ -91,4 +94,10 @@ export class StateRecorderImpl implements EmuRecorder {
             return 0;
         }
     }
+    
+    loadControls(frame : number) {
+        if (this.platform.loadControlsState)
+            this.platform.loadControlsState(this.framerecs[frame].controls);
+        setNoiseSeed(this.framerecs[frame].seed);
+    }
 }
diff --git a/src/ui.ts b/src/ui.ts
index d49a9329..da260b02 100644
--- a/src/ui.ts
+++ b/src/ui.ts
@@ -406,6 +406,7 @@ function setCompileOutput(data: WorkerResult) {
     if (rom) { // TODO instanceof Uint8Array) {
       try {
         clearBreakpoint(); // so we can replace memory (TODO: change toolbar btn)
+        _resetRecording();
         platform.loadROM(getCurrentPresetTitle(), rom);
         if (!userPaused) _resume();
         current_output = rom;
@@ -550,6 +551,7 @@ function clearBreakpoint() {
 }
 
 function resetAndDebug() {
+  _disableRecording();
   if (platform.setupDebug && platform.readAddress) { // TODO??
     clearBreakpoint();
     _resume();
@@ -693,6 +695,12 @@ function _disableRecording() {
   }
 }
 
+function _resetRecording() {
+  if (recorderActive) {
+    stateRecorder.reset();
+  }
+}
+
 function _enableRecording() {
   stateRecorder.reset();
   platform.setRecorder(stateRecorder);
@@ -790,8 +798,8 @@ function setupReplaySlider() {
     stateRecorder.callbackStateChanged = () => {
       replayslider.attr('min', 1);
       replayslider.attr('max', stateRecorder.numFrames());
-      replayslider.val(stateRecorder.numFrames());
-      updateFrameNo(stateRecorder.numFrames());
+      replayslider.val(stateRecorder.currentFrame());
+      updateFrameNo(stateRecorder.currentFrame());
     };
     replayslider.on('input', sliderChanged);
     replayslider.on('change', sliderChanged);
diff --git a/test/cli/testplatforms.js b/test/cli/testplatforms.js
index 4add131e..0a281689 100644
--- a/test/cli/testplatforms.js
+++ b/test/cli/testplatforms.js
@@ -24,15 +24,16 @@ global.Log = require('tss/js/Log.js').Log;
 includeInThisContext('tss/js/tss/PsgDeviceChannel.js');
 includeInThisContext('tss/js/tss/MasterChannel.js');
 includeInThisContext('tss/js/tss/AudioLooper.js');
-
-var jsnes = require("jsnes/jsnes.min.js");
+includeInThisContext("jsnes/jsnes.min.js");
 
 var emu = require('gen/emu.js');
+var Keys = emu.Keys;
 var audio = require('gen/audio.js');
 var recorder = require('gen/recorder.js');
 var _vicdual = require('gen/platform/vicdual.js');
 var _apple2 = require('gen/platform/apple2.js');
 var _vcs = require('gen/platform/vcs.js');
+var _nes = require('gen/platform/nes.js');
 
 //
 
@@ -108,5 +109,14 @@ describe('Platform Replay', () => {
     assert.equal(platform.saveState().p.SA, 0xff ^ 0x40);
   });
 
+  it('Should run nes', () => {
+    var platform = testPlatform('nes', 'shoot2.c.rom', 70, (platform, frameno) => {
+      if (frameno == 60) {
+        keycallback(Keys.VK_Z.c, Keys.VK_Z.c, 1);
+      }
+    });
+    assert.equal(65, platform.saveControlsState().c1[0]);
+  });
+
 });
 
diff --git a/test/roms/nes/shoot2.c.rom b/test/roms/nes/shoot2.c.rom
new file mode 100644
index 00000000..abcfde40
Binary files /dev/null and b/test/roms/nes/shoot2.c.rom differ