I recently upgraded to Snow Leopard and since then I am having difficulty running Instrument to instrument my app from Xcode. The Record button would be grayed out, and nothing
I had the same issue! I could only use Instruments on my iPhone but not on iPad or iPad2! Whenever I started instruments with Xcode 4 it would just beep and the record button would be disabled..
I solved this issue by in XCode going to >Targets>Edit Scheme>Profile "yourAppName" and changing the Build Configuration from Release to Debug. Then try to profile again Product>Profile
If you get the beep again.. You will see that it says "CHOOSE TARGET" next to the record button open the drop down >Choose Target> "yourAppName" then hit record.
This solved it for me and was finally able to run instruments again!
I know this post is old but i hope it helps someone.