I have Agilent 7697A Headspace Sampler. Sometimes I need to run fine powders (e.g. salts). I have experienced sudden loss of sensitivity that went away after sampling needle was cleaned. I think this was caused by small solid particles entrained with the carrier gas.
Is there an accessory for keeping solids in the vial? For now I wrap samples in a lint-free tissues and run tissue in a vial as a blank.