Transmission line simulation

I have a very simple transmission line problem where the plotted voltage between the two different transmission lines (node N2) is zero.

The same model in LTSPICE seems to show the correct voltage at N2.

The plots of N1 and N2 are correct though.

Not saying which one is correct, just a quick verify suggests absolute potential of node N2 and X are different between LTspice and Qspice, but differentiate voltage of node N2 and X are same. Should a potential assign to node X instead of having it float? For example, connect to GND.

This seems to be a feature of the T-device in SPICE. At O-device (Lossy Transmission Line) and T-device (Lossless Transmission Line) modelling issues - LTwiki-Wiki for LTspice it is mentioned that “there is no dc connection between the input pins and the output pins (this is why both ends must have a path to ground).” If there is no path to ground, the dc voltage at the output is undefined and may take an arbitrary value.

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