Ricoh C3228 fusing @ heavy paper and address labels

[Dexor]

Machine is fusing OK in normal mode, however, some heavy paper through bypass would fuse OK for some copies, but not for all. There is an odd copy of the same run that just would not fuse well enough - how weird is that?
Fusing through bypass is especially troublesome when using Staples brand address labels.
I've tried manual but it's quite confusing, to the point machine started jamming, and I backed off some settings I put in.
Any ideas?

[Fearless V K]

You need to set the machine for 'Thick Paper' when using heavy paper or labels.

[Eric1968]

Like Fearless V K said : always tell the machine it's using thick paper. The printing speed has to be much lower for the fusing unit to fix the toner into the paper.

[Dexor]

You need to set the machine for 'Thick Paper' when using heavy paper or labels.

Well of course it IS already set for thick paper and labels, hence my post cause whatever is set for-doesn't work.