Sony issued a replacement program for some SD cards on the 18 June, 2020 relating to their SF-M series, as well as their two Tough Spec series, the SF-M (T) and SF-G (T). If your cards have an asterisk before the lower of the two serial numbers on the reverse, or starts with TR (SF-G Tough only) then your card is unaffected.
Although this was reported by DPReview which published US contact details only, if you’re in GB, Ireland, Latvia or Estonia, you can request an SD card exchange from the following link, here.
Sony state recorded footage data on the card may be damaged or may have not recorded optimally when using a camera compatible with VSC mode (Video Speed Class) cards. However, while this suggests only video is affected, we’ve experienced occasional RAW file corruption with two 64GB SF-M Tough cards purchased via Amazon UK recently. While we’ve haven’t been able to directly verify the cards were at fault, it is cause for alarm.
We’ve completed the registration for replacement cards at this link, but be warned it’s relatively easy to misidentify your product when stating the card type. We’ve claimed for one SF-M type when we should have claimed for an SF-M T. You also have to supply photographs of the front and rear of the cards, which seems sensible.