HCSR04 over etherport hangs

[criticalboot]

Setup:

1. ATMEGA644PU with microduino bootloader.
2. ENC28j60 for ethernet communication with UIPEthernet
3. Modified etherport.ino to add proximity capability ( case PING_READ added in sysexCallback ) - files attached StandardFirmataEthernetPlus_UIPEthernet_proximity.zip.
4. J5: 0.9.23

Issue:
HCSR04 is connected as in J5 wiki to the pin 22.

HCSR is giving correct values for some time, after which it is hanging/ freezing. On investigation we found that onChange is not getting any values but onData is showing constant values.
We noticed that HCSR object is only freezing whereas everything else is working as expected.

Note:
To quickly check we connected the same via serial-port it apparently is working fine.

var this.pinTrig = 22;
this.usSensor = new five.Proximity(
      {controller: 'HCSR04', pin: this.pinTrig}
);
this.usSensor.on('change', data => {
          this.level = data.inches; 
};
this.usSensor.on('data', data => {
          console.log("in: ", data.inches); 
};

Question:
Not sure what is going wrong. Please help us identify where the problem could be.