Software Update Rollout — December 9, 2025

Model: WH‑CH720N

• Strengthened main body software security

• Version: 1.1.4

Model: WI‑C100

• Fixed issue where no ringing sound may occur when connecting to iPhone

• Enhanced main body software security

• Version: 1.0.8

Model: ULT WEAR (WH‑ULT900N)

• Strengthened main body software security

• Version: 2.1.0

Credit: @kunkoku

Source: https://www.sony.jp/headphone/update/?s_tc=aff_999_0_10_170686&utm_medium=aff&utm_source=001