DavecUK Hello Dave, I was not able to do a video but based on my observation this morning without the top lid:
I did not heard any weird sound or gurgling sound from the steam boiler during warm up but there were a few or weak drops of water going through the tube to the water tank, but after steam boiler had reached its temperature it stopped. Please see the picture where the tube is connected going to the water tank:
After I turn off the machine there were no gurgling sound nor any water going back to the water tank from the same tube.
I am not sure what is happening but the machine was behaving normal this morning.
Thank you in advance for the help I am getting from this forum. You guys are awesome! Have a great day!