I have been having serious call issues (no sound at all) on my A33. It didn't appear right away but a few days later. I took it twice to the repair center and the main PBA was replaced twice within 4 months. Samsung promised they'd change the device if there was a third repeated issue, and indeed I had it again but they rather declared it as a software issue and said they updated the phone. Really pissed me off because I did update my phone and they didn't even tell me which software version/patch it was upgraded to.
