Am I really the only one having issues with the stock music app? It's what I'm having the most issues with. I can't browse music through the app when headphones (or an aux cable) are plugged in; it it pauses and plays constantly and randomly selects songs. I can't listen to music and browse the web (using the stock browser, haven't tried it with Firefox); it pulls up and closes the app constantly (while still doing the pause/play thing) until I exit from the browser. I can't text and listen to music; my phone reboots. I can only get basic function from my music app using the widget or buttons that are on the standby screen (when you turn the backlight on but don't unlock), and even then, my phone will spontaneously pause music.
I share the problem with random reboots. I had random reboots on Froyo, but they were limited to one every three days or so, and so I could live with it. On Gingerbread, it's been a reboot every two hours or so.
My phone overheats in standby running Gingerbread. The only time I ever had a problem with overheating on Froyo was when I was watching movies or something, and the phone was running programs for hours straight. But on Gingerbread, my phone overheats just sitting in my bag on standby, which is insane. Since it's not overheating due to running too many programs, I'm forced to shut it off to get it to cool down.
My battery drains in standby, also insanity. On Froyo, battery was meh, but only when you had your screen running. If you wanted to preserve battery on Froyo, all you had to do was put it on standby and it'd last all day. On Gingerbread, the only way to keep my battery where it is is to shut it off, because it drains even on standby. I will admit that the battery lasts surprising long when it's on 5%, though.
I have a problem with 3G connectivity. On Froyo, there was never a hiccup in my 3G. On Gingerbread, I'm only connected to 3G half the time, and 3G coverage is available here. Half the time I'm only on 1X.
My Yahoo! no longer syncs automatically. I used to get notifications for Gmail and my Yahoo! (via the stock email app) to the taskbar. Now I only get Gmail. To check my Yahoo!, I have to manually enter the app and refresh to receive emails, at which point they display on the taskbar. A bit redundant. And this only works half the time. The other half of the time, I get error messages about how it's unable to connect to the internet, even though I'm connected and can browse the web.
