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Sennheiser CX 400BT Black True Wireless Bluetooth Earphones


Barcode: 4044155251753

  • Format: True Wireless

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Delivery to the UK only
Free UK delivery on orders over £20

Usually dispatched within 24 hours
Click & Collect

Get it delivered to a store near you with FREE Click & Collect available on this product. (Temporarily excluding stores in Northern Ireland & Scotland)

Ring & Reserve

Can't wait to get your hands on this? Ring to reserve at your local store, subject to availability: 03333 230 667 ⠀⠀⠀⠀⠀ (Temporarily excluding stores in Northern Ireland & Scotland)

  • Description

  • Delivery and Returns

  • Description

    Enjoy the superior sound of Sennheiser with the CX 400BT True Wireless earbuds. You can tailor the audio to your taste with customisable touch controls, and they stay comfortable and charged all day with ergonomic design and a total of twenty hours battery life with their sleek charging case.

    Superior Sennheiser sound & control
    The bespoke speaker drivers of the CX 400BT deliver high fidelity sound with deep bass, natural mid-range, and clear and detailed treble. Perfect whether you’re enjoying calming tunes or uptempo beats. You can also personalise your listening with built-in equalisers to tailor the sound to precisely your taste.

    Touch sensitive control
    Customizable touch controls on both earbuds make it easy to stay connected, whether you’re on the beat, on the ball, or on-call. A touch sensitive interface gives fast access to voice assistants like Siri and Google Assistant, as well as intuitive control of your music and calls.

    Premium sound on any device
    Whether you’re listening on iOS or Android, you’ll always receive the premium sound quality of these earbuds. Supporting a wide range of audio codecs, including SBC, AAC and aptX technologies, outstanding sound is assured on any mobile device.

    Long battery life
    You’ll never miss a beat throughout the day with a total of 20 hours of battery life. They last for 7 hours off a single charge, with a further 13 hours’ worth stored in their sleek, small and compact charging case.

    Minimalist design & stylish comfort
    The CX 400BT have an ergonomic design created for all-day wearing comfort. Ideal whether you’re enjoying a long playlist, a gripping audiobook, or an extended phone call.

    These True Wireless headphones are compatible with all smart devices with Bluetooth, including from Apple, Samsung and Google, and other Android smart phone brands.

    Product Features
    • Automatic on/off functionality
    • Up to 20 hours of music playtime
    • Approx. 1.5 hours charging time
    • Bluetooth 5.1​
    • Wide range of Bluetooth audio codec support (SBC, AAC & aptX codecs support)
    • Customisable ​touch controls
  • Delivery and Returns

    When will my order arrive?

    • If the items are in stock, we’ll aim to dispatch them within 24 hours of your order being placed. Due to the increased volumes of orders being received and the social distancing measures that our warehouse teams are following, there may be a slight delay with dispatching orders, and we thank you for your patience. 
    • Orders sent via Royal Mail 48® are usually received within two to five working days, including Saturdays. Due to current delays, please allow seven days for delivery.
    • Orders sent via the Royal Mail 24® service will be dispatched the same day if ordered by 2pm, Monday to Friday (excluding public holidays).
    • We will aim to dispatch pre-orders so that you receive them on the release date.
    • Where an item is 'Back in stock soon', we'll aim to receive more stock within a week and will dispatch any orders once the shipment has arrived.
    • Certain items can take longer to source than the estimated week, particularly during busy trading periods and may take longer to arrive at the warehouse. In this instance, we'll send weekly updates to keep you aware. 

    Delivery charges

    • Free delivery is available for most items when the order exceeds £20, but any exceptions will be clearly highlighted.
    • Selected items are only available for delivery via the Royal Mail 48® service and other items are available for delivery using this service for a charge.
    • Selected items are only available for delivery using Click & Collect to an hmv or FOPP store of your choice.
    • All delivery options and any charges that are applicable will be shown at the checkout.

    Will you tell me when my order is on its way?

    • We will email you as soon as each item is ready to be dispatched so you know when to expect them, but you can also check the status of your order in your account.
    • We don’t always ship everything together so check your dispatch email for more details - we’ll send you a dispatch email per parcel.
    • If your order contains items that are out of stock, we’ll ship the in-stock items as soon as we can and will dispatch the out-of-stock items as soon as we’ve received more stock in the warehouse
    • For items that are dispatched using our standard service, we ask that you wait 14 days from the date of dispatch before reporting any items as undelivered.


    • Due to current lockdown measures that are in place across the country, we have extended our returns policy and items ordered from October 2020 can be returned to us up until 30 days after our high street stores reopen.