I brought the Stanmore 3 a few days ago. The RCA connections and being able to connect a turntable were a big draw for me to choose this model over the smaller ones. I've had a very disappointing experience with it in that regard though and I'm wondering if it's normal, or could there be an issue with the speaker itself.

The Bluetooth is no problem at all. Sounds great. When I switch to the turntable and RCA though, it gives off a fairly substantial humming type sound. It's very annoying. I've tried moving everything, I've had the turntable apart to check connections (even though it too is brand new), and I've even tried a different device, using different RCA cables. Still the same issue persists.

Anyone experienced this with their Stanmore?