Media resource: validator error on correct media subtype codes

I’m developing a simple message to send a scanned document for filing, using Media resource, & getting the following output from the validator, both in DSTU2 and in current build downloaded 18th Oct.

ERROR @ /f:Bundle/f:entry[2]/f:resource/f:Media/f:subtype/f:coding (line 48, col29) Error validating code “scan” in system “”: null (src = InstanceValidator)

The value ‘scan’ is in the value set both as described in the spec(s) and in the valuesets xml. data. Any thoughts?