diff --git a/config.h b/config.h
index 9871909..b29837d 100644
--- a/config.h
+++ b/config.h
@@ -6,7 +6,7 @@
 //try to keep this in sync.
 //SavvyCAN will complain if you connect a GVRET board with a revision
 //less than this number.
-#define CURRENT_GVRET_VER   321
+#define CURRENT_GVRET_VER   322
 
 #endif // CONFIG
 
diff --git a/frameplaybackwindow.cpp b/frameplaybackwindow.cpp
index f16c24c..83bb46e 100644
--- a/frameplaybackwindow.cpp
+++ b/frameplaybackwindow.cpp
@@ -71,6 +71,7 @@ FramePlaybackWindow::FramePlaybackWindow(const QVector<CANFrame> *frames, Serial
     playbackTimer->setInterval(ui->spinPlaySpeed->value()); //set the timer to the default value of the control
 
     connect(this, SIGNAL(sendCANFrame(const CANFrame*,int)), worker, SLOT(sendFrame(const CANFrame*,int)), Qt::QueuedConnection);
+    connect(this, SIGNAL(sendFrameBatch(const QList<CANFrame>*)), worker, SLOT(sendFrameBatch(const QList<CANFrame>*)), Qt::QueuedConnection);
 
     QStringList headers;
     headers << "Source" << "Loops";
@@ -520,7 +521,8 @@ void FramePlaybackWindow::btnSelectNoneClick()
 }
 
 void FramePlaybackWindow::timerTriggered()
-{
+{    
+    sendingBuffer.clear();
     for (int count = 0; count < ui->spinBurstSpeed->value(); count++)
     {
         if (!playbackActive)
@@ -537,6 +539,7 @@ void FramePlaybackWindow::timerTriggered()
             updatePosition(false);
         }
     }
+    emit sendFrameBatch(&sendingBuffer);
 }
 
 void FramePlaybackWindow::updatePosition(bool forward)
@@ -606,13 +609,26 @@ void FramePlaybackWindow::updatePosition(bool forward)
     }
 
     //only send frame out if its ID is checked in the list. Otherwise discard it.
-    const CANFrame *thisFrame = &currentSeqItem->data[currentPosition];
+    CANFrame *thisFrame = &currentSeqItem->data[currentPosition];
+    int originalBus = thisFrame->bus;
     if (currentSeqItem->idFilters.find(thisFrame->ID).value())
     {
         //index 0 is none, 1 is Bus 0, 2 is bus 1, 3 is both, 4 is from file
-        if (whichBusSend & 1) emit sendCANFrame(thisFrame, 0);
-        if (whichBusSend & 2) emit sendCANFrame(thisFrame, 1);
-        if (whichBusSend & 4) emit sendCANFrame(thisFrame, thisFrame->bus);
+        if (whichBusSend & 4)
+        {
+            sendingBuffer.append(*thisFrame);
+        }
+        if (whichBusSend & 1)
+        {
+            thisFrame->bus = 0;
+            sendingBuffer.append(*thisFrame);
+        }
+        if (whichBusSend & 2)
+        {
+            thisFrame->bus = 1;
+            sendingBuffer.append(*thisFrame);
+        }
+        thisFrame->bus = originalBus;
         updateFrameLabel();
     }
 
diff --git a/frameplaybackwindow.h b/frameplaybackwindow.h
index d6e2a2d..07296dd 100644
--- a/frameplaybackwindow.h
+++ b/frameplaybackwindow.h
@@ -55,11 +55,13 @@ private slots:
 
 signals:
     void sendCANFrame(const CANFrame *, int);
+    void sendFrameBatch(const QList<CANFrame> *);
 
 private:
     Ui::FramePlaybackWindow *ui;
     QList<int> foundID;
     QList<CANFrame> frameCache;
+    QList<CANFrame> sendingBuffer;
     const QVector<CANFrame> *modelFrames;
     int currentPosition;
     QTimer *playbackTimer;
diff --git a/serialworker.cpp b/serialworker.cpp
index c033522..3238fff 100644
--- a/serialworker.cpp
+++ b/serialworker.cpp
@@ -70,11 +70,11 @@ void SerialWorker::setSerialPort(QSerialPortInfo *port)
     serial = new QSerialPort(*port);    
 
     qDebug() << "Serial port name is " << port->portName();
-    serial->setBaudRate(serial->Baud115200);
+    serial->setBaudRate(10000000); //more speed! probably does nothing for USB serial
     serial->setDataBits(serial->Data8);
-    serial->setFlowControl(serial->HardwareControl);
+    serial->setFlowControl(serial->HardwareControl); //this is important though
     serial->open(QIODevice::ReadWrite);
-    serial->setDataTerminalReady(true);
+    serial->setDataTerminalReady(true); //you do need to set these or the fan gets dirty
     serial->setRequestToSend(true);
     QByteArray output;
     output.append(0xE7); //this puts the device into binary comm mode
@@ -85,6 +85,8 @@ void SerialWorker::setSerialPort(QSerialPortInfo *port)
     output.append(0x07); //request device information
     output.append(0xF1);
     output.append(0x08); //setting singlewire mode
+    output.append(0xF1); //yet another command
+    output.append(0x09); //comm validation command
     if (settings.value("Main/SingleWireMode", false).toBool())
     {
         output.append(0x10); //signal that we do want single wire mode
@@ -122,6 +124,7 @@ void SerialWorker::connectionTimeout()
         //then emit the the failure signal and see if anyone cares
         qDebug() << "Failed to connect to GVRET at that com port";
         ticker->stop();
+        closeSerialPort(); //make sure it's properly closed anyway
         emit connectionFailure();
     }
 }
@@ -171,6 +174,14 @@ void SerialWorker::sendFrame(const CANFrame *frame, int bus = 0)
     serial->write(buffer);
 }
 
+//a simple way for another thread to pass us a bunch of frames to send.
+//Don't get carried away here. The GVRET firmware only has finite
+//buffers and besides, the other end will get buried in traffic.
+void SerialWorker::sendFrameBatch(const QList<CANFrame> *frames)
+{
+    for (int i = 0; i < frames->length(); i++) sendFrame(&frames->at(i), frames->at(i).bus);
+}
+
 void SerialWorker::updateBaudRates(int Speed1, int Speed2)
 {
     QByteArray buffer;
diff --git a/serialworker.h b/serialworker.h
index c0ff1ce..0b3c3b7 100644
--- a/serialworker.h
+++ b/serialworker.h
@@ -50,6 +50,7 @@ public slots:
     void setSerialPort(QSerialPortInfo*);
     void closeSerialPort();
     void sendFrame(const CANFrame *, int);
+    void sendFrameBatch(const QList<CANFrame> *);
     void updateBaudRates(int, int);
     void stopFrameCapture();
     void startFrameCapture(); //only need to call this if previously stopped. Otherwise it's the default