Question:

Why are CLM materials are displaying twice in the Media tab?  This happens only for content which is uploaded through the use of CLM Vault integration. 

Answer:

This is the standard behavior of the CLM-Vault integration if the Include Non Steady State flag in CLM Administration Console is enabled for the Sandbox. This allows the integration to keep a staged version of the CLM Presentation next to the approved one.

Related Documentation:

CRM Help Documentation: Using the CLM Admin Console

Thank you