 /* timer variables */
 unsigned long currentMillis;        // store the current value from millis()
 unsigned long previousMillis;       // for comparison with currentMillis
-unsigned int samplingInterval = 19; // how often to run the main loop (in ms)
+unsigned int samplingInterval = 25; // how often to run the main loop (in ms)
 
 /* i2c data */
 struct i2c_device_info {

  // pins configured as analog
}

/*==============================================================================
 * SYSEX-BASED commands
 *============================================================================*/

void sysexCallback(byte command, byte argc, byte *argv)
{
  byte mode;
  byte stopTX;
  byte slaveAddress;

  if (currentMillis - previousMillis > samplingInterval) {
    previousMillis += samplingInterval;

    if (pingLoopCounter++ > numLoops) {
      pingLoopCounter = 0 ;
      if (numActiveSonars) {
        unsigned int uS = sonars[nextSonar]->ping();
        // Convert ping time to distance in cm and print
        pingResult = uS / US_ROUNDTRIP_CM ;
