Using an Op-amp buffer to Power Amplifier unit
The circuit you show is almost guaranteed to oscillate. The 1K resistor makes it worse. It also can't handle much ground current before the op-amp saturates (due to the 1K). 

Something more like this has a better chance of working: 







simulate this circuit &ndash; Schematic created using CircuitLab

Since we don't know how much ground current there is, it's hard to design it properly. You may need a beefier buffer than an LM324 which is only capable of 10s of mA. If the load is grounded vs. a bridging amplifier it's probable unsuitable for anything more than a headphone amplifier. On the other hand, if the 4558 directly drives the output, it may be okay.