A lot of things can affect how well your phone is working, but it might be news to you that one of those things is your own body. A recent report (PDF) commissioned by the Nordic Council of Ministers examined the antenna performance of different smartphone models and found that both the hand you hold your phone in and the ear you hold it up to can dramatically change how well it’s picking up radio signals.

In the chart below—created by Quartz and shared by Digg—you can see some of the specifics (dBm stands for decibel-milliwatt). In brief: iPhones do not fare well. The iPhone SE, 6S, and 6S Plus all rank pretty poorly overall, and those models operate particularly poorly if you hold them in your left hand and to your left ear.

While this might seem like some 21st century subtle discrimination against southpaws, it’s actually just a failure of tech when it comes to antenna placement, which varies from phone to phone. It’s not all bad news, though. The Microsoft Lumia 640 has the best call transmission strength overall, regardless of which hand you hold it in, and some phones—like the Samsung Galaxy S6 Edge—do actually work better in your left hand. In general, though, the right hand and right ear combination is your best bet for a clear call.

So next time you’re in the middle of a conversation and switch hands, only to find that the call has suddenly become a little fuzzy, it’s not just in your head. We might not be able to manually futz with the antenna like we used to, but it’s still a fickle piece of hardware.

[h/t Digg]

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