A patient referred to physical therapy with a diagnosis of “…

A patient referred to physical therapy with a diagnosis of “dizziness” reports the following during subjective history: Symptoms began 1 week ago and are intermittent. They are described as “room spinning” and last 30 seconds when the patient transitions from sit to supine or rolls over onto their side in bed. Mild associated nausea noted at first, but has improved. There are no symptoms at rest or with generic head movement.  No cochlear complaints reported  No red flag signs Which vestibular condition is MOST likely based on this subjective history?