Yes. However you will need to configure iTunes so that it treats the My Cloud as the default library location. Once the media is stored on the My Cloud any iTunes enabled device should be able to access that media provided one has enabled the iTunes option within the My Cloud Dashboard (Dashboard > Settings > iTunes > iTunes Server = On). One also will have to ensure Media Serving is enabled on each Share containing the media files (Dashboard > Shares > Media Serving = On). Also any DLNA client will access and play any supported media content stored on the My Cloud.
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