If you ever encounter this exception:

Exception of type 'Microsoft.Dynamics.AX.Framework.Services.Metadata.Exceptions.MetadataItemException`1[Microsoft.Dynamics.AX.Framework.Services.Metadata.Contracts.FieldGroupMetadata]' was thrown.

When

1) Printing a SSRS Report
2) Refreshing the DS from AX VS SSRS solution
3) Deploying a report from command line

It means there's good probability one of your tables field groups contains fields that the table does not have anymore.

This can be introduced by code merge or model installation, so be aware =)