Arctic has issued a recall, saying some recent batches suffer a "premature hardening" issue.
"Current findings from our permanent quality assurance tests show that certain batches of our MX-5 thermal compound contain anomalies in consistency and shelf life. The affected products show an increased separation of oil within the paste, resulting in premature hardening. This can lead to adverse effects and application difficulties," Arctic explains.
Arctic knows exactly which batches are problematic and is in the process of removing them from circulation. However, that doesn't do you much good if you already purchased an affected tube, or managed to get one that is still stocked somewhere. There's good news, though—Arctic is offering to replace bad batches for free.