No dialog Orphan Black

Yes, you are correct on how it is likely an AMC ( AMC+) issue. If you have already contacted them regarding the issue and they weren’t of much help, that’s about all you can do as a customer. Since you already reported the issue to them, hopefully they will perform the correct steps to try to resolve the issue.

Since I am subscribing to AMC+ through DirectTV Stream, AMC+ has no way to confirm that I am a subscriber.  AMC+ referred me to DirectTV Stream.  Two CSRs at DirectTV Stream had me jump through a bunch of hoops (resetting, logging out, logging in, removing AMC+ app, reinstalling AMC+ app, etc) but the problem remains.  This is clearly an AMC+ content issue, not an equipment issue, however, nobody at DirectTV Stream will engage AMC+ to fix the problem.  My only recourse is to cancel my AMC+ subscription. 

Yep. You may need to subscribe directly to AMC+ in order to actually get your subscription working properly. This obviously isn’t the best solution since you were getting a discount by bundling with DIRECTV service. 

After weeks of back and forth with both DirectTV Stream and AMC+ I have given up trying to get the issues with the audio (no dialog) on Orphan Black resolved.  I cancelled my AMC+ subscription through DirectTV Stream today.  I plan to cancel my subscription to DirectTV Stream shortly.  Worst customer service experience I've ever had.  If capitalism worked, DirectTV Stream would be out of business.