Issues with iPhone 16 Pro Max – Speaker and Screen

Since I bought my iPhone 16 Pro Max, I’ve been experiencing two issues. The first one is with the top speaker – when I increase the volume past halfway, the microphone starts to crackle. This is especially noticeable during phone calls, and the sound quality becomes very bad. The second issue is that sometimes, out of nowhere, the screen stretches for a split second, and I see green, black, or other colored lines. These lines appear in different parts of the screen, especially when I turn it on or in certain apps. Even the Always-On Display sometimes glitches. I’m starting to wonder if the phone is defective or if it’s a software issue, as updating to iOS 18.0.1 hasn’t fixed it. Does anyone else have this problem with the new iPhone?