pseudoMRM transitions

Riddle me this. We've encountered a rather strange phenomena when optimising MRM transitions on a Agilent Ultivo TQ. The MS does not have any issues in generating the precursor ion for example 897.5 (216V fragmentor) but fail to generate a product ion. 

The optimisor will give you 897.5 - 897 transition at 1V CE. Manual optimisation does not improve on this and it continues to give these PseudoMRMs. This happens with many 'larger' compounds with masses between 700-1400, it seems to generate a SIM without problems but provides you with a pseudoMRM at a very low CE voltage. Running in SIM mode provides roughly 10X more sensitivity than these pseudoMRMs. Smaller compounds have no problem whatsoever and generates the expected MRM transitions. I've noticed this phenomena on both the Ultivo but also on a 6470 model. Has anyone out there experienced this?

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