Frequently, people with dementia exhibit abnormal behaviors that may cause self-injury or burden their caregivers. Some audible manifestations of these problematic behaviors are of vocal nature (e.g., shouting, mumbling, or cursing), others are environmental sounds (e.g., tapping or slamming). The timely detection of these behaviors could enact non-pharmacological interventions which in turn can assist caregivers or prevent escalation of the disruption with other fellow residents in nursing homes. We conducted a field study in a geriatric residence to gather naturalistic data. With the participation of five residents for 203 h of observation and of the 242 incidents of problematic behaviors were registered, 85% of them had a distinctive auditory manifestation. We used a combination of standard speech detection techniques, along with a novel environmental sound recognition methodology based on the entropy of the signal. We conducted experiments using realistic data, i.e., audio immersed in natural background noise. Based on classification results with F1 score above 87%, we conclude that audible cues can be used to enact non-pharmacological interventions aimed at reducing problematic behaviors, or mitigating their negative impact.