iPhone 4 isn’t the only iDevice with antenna issues. I just picked up a set of Nuvelli NUV2882 Bluetooth stereo earphones, and I’ve found that their reception suffers if I touch certain areas on both my iPad and my iPhone 3GS. On the iPad, sound starts cutting out if I touch the metal near the speaker grill. On the iPhone, it happens when I touch around the edges of the screen.
Most irritatingly, it grounds when it’s in my pocket, making the headset almost useless. Interestingly, the effect is worst when the headset is in stereo mode; when taking calls (which are mono), the sound merely crackles occasionally, whereas when listening to music the sound cuts out entirely.