Rotel RTX-1058 MCU keeps DSP in reset

Hey guys,

I would appreciate some ideas based on your experience.

I am playing now with Rotel RSX-1058. There is no sound coming out of this receiver.
1) It powers up, there is a working communication between the main MCU and the front panel MCU as well as with the volume control & input selection ICs (I verified that they work)
2) The MCU keeps the output stage of the preamp in mute
3) The MCU keeps the DSP in reset state, therefore the sound goes through (if we forget mute=on) only in 'Bypass' mode, where the DSP is not used.
4) All the supplies seem OK
5) Both the MCU and the DSP oscillators are working fine

It's not hugely common receiver but based on your experience with perhaps some other devices - any ideas what typically goes wrong?

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Thanks!