Sennheiser PXC 550-II vs. Sennheiser HD 450BT - SoundGuys
PXC550 won't hold >20% charge and runs out quickly. Cracked the case to check buttons and found an extra 'music' button. Anyone else had this issue? : r/sennheiser
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User manual Sennheiser PXC 550-II (English - 38 pages)
Amazon.com: Sennheiser PXC 550 Wireless – NoiseGard Adaptive Noise Cancelling, Bluetooth Headphone with Touch Sensitive Control and 30-Hour Battery Life : Electronics
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