I acquired an excellent vintage amplifier and started the journey of giving it a new life. I have managed to repair most of the damage and have come to a working device.
But there is one problem still to solve. In the attached image there are 9 resistors marked in red. With the help of a thermal camera, I discovered that the resistors are getting hot: 100-130°C. The temperature when the amplifier gets an input signal is the same as in standby without an input signal.
I measured the resistors in question and they are all in range. The main voltage rails are a bit higher, 62V is 65V, and 58V is 61V. The voltage drop across transistors is the same. Taking into consideration the transistor voltage drop, with the higher input voltage, the voltages on the resistor are in good condition.
So if anybody has an idea or a proposal for the next step I would really appreciate it.
Thermal images of the problematic spots:
Hotspots are marked with a red circle: