Just to be sure I installed beats audio this morning and I have no problems, sound works, recovery is still normal. What you have described is exactly what happens when updating OTA with xolo, I know as I done it when I was trying to keep root through OTA. When you try fixbrick are you in bootloader mode ? that is how I recovered.
I know you said you did not use the OTA but what you describe is same so worth a shot:
From a booted device start rickywyatt tool as it does not see device if you start in bootloader and wont load (at least for me anyway)
Now boot into bootloader and then press fixbrick, this way is different to using fixbrick from booted, it somehow bypasses the screwed recovery.
It will look like it cannot find device but wait and it will.............
If that don't work that way follow rickywyatt instruction on how to use the fastboot tool to recover device.
Edited by jikobutsu, 29 November 2012 - 10:54 AM.