The question that must first be answered is, "what is truth". Without that, we're just chasing after wind. Or perhaps the question you're asking isn't so much about whether we believe truth to be subjective or objective but rather to discover just what we perceive truth to be. Do we define truth as simply the nature of the world as the observer earnestly believes it to be or do we define truth as an entity that exists on its own and independantly of any and all observers?
If truth is simply the world as it is genuinely perceived then there is no question that it must be subjective. Yet, this view leaves me with a bad feeling. Not least of all, the specification of "genuinely perceived" requires some form of absolute as a base, else it is meaningless and we may as well say that truth is the world as we choose to see it. The idea that even so-called relative truth must be based on a "true" perception impicitly defines truth as an absolute. The madman does not choose to be mad, but in objective truth the madman perceives his own subjective truth.
Yet, if truth is objective, what then? That which is truly objective is un-knowable to man as we are limited to such information as we gather from our senses which leaves us with knowledge only of our own subjective perceptions. If our senses are flawed, we cannot know it save by comparison to a normative set of senses. But what when the normative value is itself flawed? We could not ever detect that condition.
So we have then the two options. If truth is subjective, we are left with an implicit demand for objectivity in at least one instance and that discontinuity creates instability. Yet if truth is objective, it is then un-knowable and this is painful to admit that we are helpless to discover the ultimate.
For myself, I am inclined towards the latter. Defining truth as objective is at least consistent, and I've known enough instability to prefer the pain of an un-knowable to the self deception of inconsistency.
ZV