This study aims to investigate the clinical performance of the Osia 3 Sound Processor in comparison to the Osia 2 Sound Processor in adults with mixed or conductive hearing loss or single-sided deafness implanted with an Osia implant. Participants will attend four study visits, where they will complete various hearing assessments using the Osia sound processors.

Inclusion Criteria:

• Implanted with a Cochlear Osia Implant (OSI100 or OSI200)
• Conductive or mixed hearing loss in the implanted ear. Bone conduction threshold 4-frequency pure tone average (PTA4; mean of bone conduction thresholds at 0.5, 1, 2 and 4 kHz) ≤ 55 dB HL.

OR Single-Sided Deafness in the implanted ear. Air Conduction threshold 4-frequency pure tone average (PTA4; mean of air conduction thresholds at 0.5, 1, 2 and 3 kHz) ≤ 20 dB HL in the good ear.

• Aged 18 years or older, at time of consent.
• Minimum experience of 1 month with the Osia 2 Sound Processor.
• Fluent speaker in the language used to assess speech perception performance.
• Willing and able to provide written informed consent.
• For voluntary visit Aqua+ in water only: Be comfortable with going into a swimming pool and putting head under water.

Exclusion Criteria:

• Sensitivity to loud sounds.
• Ongoing infection at or around the sound processor area.
• Unable or unwilling to comply with the requirements of the clinical investigation as determined by the Investigator.
• Use of ototoxic drugs that could be harmful to the hearing, as judged by the investigator
• Investigator site personnel directly affiliated with this study and/or their immediate families; immediate family is defined as a spouse, parent, child, or sibling.
• Cochlear employees or employees of Contract Research Organisations or contractors engaged by Cochlear for the purposes of this investigation.
• Current participation, or participation in another interventional clinical study/trial in the past 30 days, involving an investigational drug or device (unless the other investigation was/is a Cochlear sponsored investigation and determined by the investigator or Sponsor to not impact this investigation).

Cochlear do not have an approved platform for public sharing of IPD collected in this study. Data may be provided to individual researchers on request.