UNLABELLED: Recent advances in sleep medicine have led to the development of various validated diagnostic devices for obstructive sleep apnea. Despite limitations, there has been an increase in the use of home sleep apnea tests. The accuracy of home sleep apnea tests may be limited by the inability of their automated signal analysis to differentiate between artifacts and the target physiological signal, leading to erroneous test interpretations with management implications. We present a 60-year-old male with a mechanical heart valve diagnosed with obstructive sleep apnea. At the 6-month postintervention follow-up, the home sleep apnea test report indicated loud snoring 100% of the time. After carefully reviewing the raw home sleep apnea test data and history, the source of the nonphysiological high-level sound was identified as the mechanical heart valve, and the patient was reassured. This case highlights how trusting only automated analysis can miss important information and arrive at misleading conclusions. CITATION: Wireko FW, Morgenthaler TI. Home sleep apnea testing auto-interpretation.