The sound of squeaking has been attributed to the spectral dolphins; they were kept in a tank in the basement in the 1970s and would be winched up to the stage where they would perform tricks to the delight of theatre-goers. They would sadly died of neglect, but the tanks and lifting mechanism are still to be found below the stage apparently.
Update: 20/2/20: Staff member Howard Clark informs me, "We are aware of these historical reports. I am unfortunately unable to confirm their truth."
Link: Shady Old Lady
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