I don't have a K10d anymore but I can tell you for certain my K20d does not behave this way and I can assure you as well, my K10d did not. Neither did my K7 nor my K5. The only time M behaved remotely like this was / is, on the K7/5 if using an A type lens, set exposure (in M), half press and try to readjust one or the other (aperture or shutter speed). It behaves as if the exposure is locked and will compensate one setting for the change in the other. On the K20d, if the shutter button is half pressed and one setting is changed, the other stays the same. Regardless of what happens, one of the e-dials must be turned to change anything.