Electro Harmonix 'Rams 'Head' Question

[alteredsounds]

Bought an old EH Rams Head Muff recently.  Got time to plug it in today and there seems to be a very strong octave effect going on most settings.  I've got many old muffs but not heard a Rams Head before so am unsure if this is right?  There has been no mods or fixes of any kind done to it.  Anyone have Rams Head experience or can explain the octave fx's happening?

Cheers,
Nick,

[AC30Dirty]

Does the pedal have any Germaniums in it? Check the clipping stages and the feedback loop of the Q3 transistor. I read germaniums in these sections of the pedal produce an octve sort of tone. Hope this helps.