What could cause something to sound exactly like footsteps, at about 01.00, to go down a hallway and do it only once in the 4 years I lived in that house?
The problem is that we have no way of determining if it sounded exactly like footsteps.
We have no way of determining if any actual noise was made at the time. We have no way of determining that what you heard did actually sound like footsteps, instead of sounding ambiguous and being interpreted as footsteps by your mind in that moment.
We have no way of determining whether it sounded nothing like footsteps at the time, but over the years of re-telling and re-remembering the re-told story, the narrative has evolved to "sounded exactly like footsteps."
We have no way of determining that it only happened once in 4 years. We have no way of determining whether it actually happened a lot, but only that one time were the circumstances such that it created the impression of footsteps and stuck in your mind. We have no way of determining whether it's a sound that your house makes all the time, but it just happened to sound different when you heard it from the other direction that once. Etc.
We have no way of determining whether this happened to a friend of yours, and you're relaying it in the first person for greater impact, but misremembering some of the details your friend imparted to you. We have no way of determining whether this friend actually experienced the event in the first place. Etc.
We have no way of determining whether this incident, or any incident remotely like it, actually happened to anybody at all. We have no way of determining that this isn't a invented narrative being presented as fact, to pose a challenge to the skeptical epistemology of ghosts.
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So no. "What could cause something to sound exactly like footsteps?" is the wrong question. The right question is, "without a recording of the sound, without actually investigating possible causes of noise in that house, why on Earth would you imagine this anecdote supports the idea of ghosts?"