Modpack version
1.70c
appliedenergistics2-rv6-stable-6.jar (there does appear to be an update for this available, or at least twitch client says so)

Issue
AE2 memory cards not working on p2p tunnels.
Right Clicking p2p says "Invalid Machine"
Shift Right Clicking p2p says "Memory Card Cleared"

Was working in 1.69 and prior.

Logs
here's the relvant output from latest.log

[22:09:31] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:32] [Client thread/INFO]: [CHAT] Memory card cleared.
[22:09:33] [Client thread/INFO]: [CHAT] Memory card cleared.
[22:09:40] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:42] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:43] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:43] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:44] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:44] [Client thread/INFO]: [CHAT] Invalid Machine.
[22:09:47] [Client thread/INFO]: [CHAT] Memory card cleared.

Let me know if you need anything else

Thank you for the report, I will investigate the issue.

I know this happens when you are wearing a shield (or any item for that matter, but I'm not sure) in your off-hand.

Thinking about it I might have had a Draw key in my off hand. Will re-test tonight after work.

Yep, confirmed works fine with nothing in offhand. With anything in the offhand it fails.

I guess this is more of an AE2 issue then, but good to know.