Cardo Scala Rider Q3 Multiset. One unit NOT working

Please read full description.

This item has been relisted. Originally sold over a month ago as brand new. Before I listed item I did check it all over and all worked as it should. However, the buyer (0 feedback) asked if he could return it as one unit was not charging. I'm a decent person so agreed despite being sure it was fine. 

Since receiving it back I've checked it and one if the units is not charging as the buyer suggested. When it's plugged in the blue light flashes, then turns red. I have no idea if it can be repaired so assume you are buying just the one. 

Before I sold it I was messaged by someone (with 0 feedback) asking if I'd sell just one. It could be, that it was purchased and one of the working units was swapped for a faulty one.

Do not bid if your feedback is below 50 

Below is the original listing.

I was given this for Christmas a few years ago but never used it. It's never been used and only taken out of the packaging so I could take the pictures. 

This is the multipack which contains 2 systems (enough for 2 helmets/people).

Below are some of the features:

Bike to Bike intercom with up to 4 bikes over a range of up to 1km.

Click-to-Link - For spontaneous intercom with other Scarla riders nearby.

Music Sharing - Rider and passenger can listen to the same stereo music (via  A2DP).

Cardo SmartSet app for on the go customization.

Cardo Community Platform to customise settings and receive software updates via your MAC or PC.

Interchangeable Hybrid and corded microphones included to fit virtually all helmets.

Dual replaceable speakers (3.5mm).

Make/Receive/Reject calls by voice command or at the push of a button

*Dual Handsfree profile to connect 2 mobile phones simultaneously.

*A2DP/AVRCP profile for wireless stereo from smartphones..

Receive GPS navigation voice instructions via Bluetooth.

Built in FM Radio with RDS

*6 station presets with auto scan

*Automatic selection of the strongest signal.

*Radio on time 7-10 hours.

*Automatic Radio muting for incoming calls and GPS instructions.

Connect to MP3 players and mobile phones for Bluetooth stereo music (A2DP).

Hot-Dial number (Customisable).

Self-adjusting speaker volume according to speed and ambient noise (Customisable).

Packet Loss Concealment, Real-time compensation of audio losses in challenging environments.

Voice control for receiving/rejecting incoming mobile or intercom calls (customisable).

Digital Signal Processing for advanced audio functionality.

Up to 8 hours talk time. 1 week standby (recharging from wall outlet or USB connection).

Waterproof and Dustproof