Sennheiser Professional HD 280 PRO Over-Ear Studio Monitoring Headphones -Faulty Right Ear

Right Ear Not Working No Sound- Boxed with 6.35mm Jack Plug, In Good Physical Condition. Please see images for Example of Item Shipping.
These are used headphones so will show some scuffs or marks from usage.
No Sound in Right Ear do selling For Parts Not Working
This may be an Easy Fix for Someone or Good for Spares.

The sound is completely dead in the ear opposite to where the cable attaches to the HD 280 pro

Because the main audio cord attaches to the left ear cup, a completely dead right side points directly to a broken internal headband wire or a disconnected solder joint inside the left ear cup. The right channel signal travels from the main cable, into the left ear cup, through a hidden wire routed across the headband, and down into the right speaker.

The most frequent culprit is fatigue in the headband wire caused by repeatedly adjusting the headphone size sliders. 

CLOSED BACK studio headphonesThe HD 280 Pro is Sennheiser's most significant closed, around-the-ear headphone to be introduced in years. Designed to exceed the demands of the professional environment, the HD 280 Pro boasts extremely robust construction combined with the sound quality, modular design and aggressive noise isolation that is necessary in the field.The unique collapsible design, combined with swiveling ear cups, offers maximum flexibility in any application!

Amazing Features• High ambient noise attenuation
• Accurate, linear sound reproduction
• Folding and rotating earcups for space-saving transport
• Soft earpads for a comfortable fit
• Tough, single-sided cable