Slight balance drift ... Help please

[Deaf Cat]

Hiya,

Just wondering if there is a basic list of components that could cause a slight balance drift as a preamp/processor warms up.

The volume control is a laser trimmed resistor ladder, there are electrolytic caps in the power and singal paths and Burr-Brown's OPA 2134 FET input op amps and a load of other SMD's that I'm not sure what they are.

Basically, I boost the left main channel by a few dB to get vocals central. I'm told a low output op amp is the cause....

After about an hour, vocals drift slightly to the left so I reduce the boost by 1/2 a dB to bring them central again, another two hours on, another reduction of 1/2dB to bring the vocals central again.

Being somewhat of a beginner in the electronics field I understand there could be a long long list of bits that could contribute to this, but the main thing that I can logically think of (not knowing much) is that one or two of the electrolytics is on the way out, in the signal path. Simply due to the fact they seem to me to be the only thing that is made in a way that may degrade with use and time.....


Any thoughts much appreciated

Thank you
DC