Definately a hardware problem, where exactly I cant say. The auto tune works by temporarily disconneting and controls to pitch, ie mater tune, pitch wheel etc. While in this state a signal is sent to each osc and the tune voltage to each osc is changed as required. My guess is that one of the logic devices that handles the initial stage has a problem and is doing something odd to other controls. The fact that you loose your programs is a little bit odd too, cant think why this could be sorry

If you have a schematic I could take a look and give some pointers.

--- In oberheim@yahoogroups.com , "dfdf" <oscillator909@...> wrote:
>
> Hello,
>
> i have a question about an Oberheim OB8 Synthesizer. This unit have a bad voice - but this in not the problem in this time. there is problem with the auto tune , after switching on, some sounds of the internal programms sounds ok - some not -strange sounds ...
>
> when i play the programs which sounds "normal" the voices get out of tune a little bit, thing this is normal. but - when i press the auto tune button, the ob will beginn to tune each voice, after finishing all LEDS on the frontpanel will flash and then, after this, no more sounds
> come out of the ob8, i can change the programs, but there is no sound .... when i try in this situation the modifiy the program with cutoff, attack, decay , nothing happens, no sound ...
>
> this is strange, the only way to play the ob8 again is to switch of the synth and switch on again...
>
> anyone have an idea
>
> greetz
>
> Phil
>