Behringer x 1204usb mixer vu meter not registering

SOURCE: type pf op amp in a Behringer XENYX 1204USB Mixer

Behringer uses 4580's in appropriate packaging everywhere. There are 339 comparators for the level indicator area.

The Mackies uses both NJM2068 and NJM4560M

The 2068' are used in most of the low noise areas and the 4560 is used in the 75Hz high pass filter for example.

SOURCE: i have a behringer xenyx

Yep ! First thing is to eliminate any processing resource "hogs" that **** respources and can cause buffer overruns. Eliminate Antivirus, antispyware, and network communication and wireless network programs running in the background while recording.
Next make sure that ALL equipment is powered from the same receptacle or power source. In your case that should be the mixer and the PC.
Next remember that the condenser mic picks up everything... I have 5 of those mics and seemingly noise free environments turn out to have little things that generate fast rising pulses that you don't notice till they are recorded.
Lastly, the air here is very dry and plain old static electricity is rampart... Lady shuffling her feet was sending pulses through the mic cable at our church. They are NOT audible until they get into the sound system as clicks.
I have found that trying to record directely to a USB stick often has ooverruns and clicks... also burning a CD from stick to the CD results in noise due to buffer underuns. Burn from Hard drive to CD and make sure all the other hog programs are shut off.