GC Using High Boiling Solvents

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Dr. Analytical
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GC Using High Boiling Solvents

I have been asked to "optimize/fix" a method for some residual solvents (IPA, methylene chloride, toluene) in a pharmaceutical.  The solvent is DMAC (dimetylacetamide).
DB-5 30M X 0.53 um X 5 um, 5 mL/min He, Inj Vol. 1 uL, Inj Port 150, Splitless for 0.3 min., Temp ramp starting at 36, FID, etc.  The main problem is peak distortion/splitting for IPA (first out) and tailing/shoulder for MC.  Toluene is OK, except for an impurity in the solvent.
For the record, this is not my method.  It's a poor column choice, the inj port is below the BP of the solvent, and who does splitless on a megabore column?
I would like to hear from anyone who has experience working with this solvent?  How have you adjusted your conditions?  Do you have similar problems, and how do you solve them?