Just sent the following email to the company that supplies my MFSL inner sleeves: Hello. I purchased a pack of Mobile Fidelity Inner Sleeves (50 Pack) on 9/24/12 order # 410915. I opened the pack this weekend after cleaning close to thirty LP's using a VPI 16.5 record cleaning machine. Last night I decided to play one of the newly cleaned LP's and noticed strange marks on the vinyl playing surface. I found this strange due to the fact that the LP was practically mint before cleaning and was absolutely clean afterwards. I checked the other LP's..and same marks. I re-cleaned two LP's this morning with MFSL Enzyme cleaner and MFSL Pure. The marks were removed and after thoroughly inspecting the vinyl they were placed in two new inner sleeves. At this time in occurred to me...maybe it's the inner sleeve leaving the marks...I pulled the vinyl out and found new marks. I then realized that the marks were being left wherever I held the inner sleeve. I then purposely touched the sleeve, with vinyl inserted, and found that wherever I touched the sleeve a mark or print was left on the playing surface. So, I then opened a new pack that was ordered on 11/6/12 order #1351. I placed a new LP (not machine cleaned yet) into one of the new sleeves and it also left marks! I then repeated the same experiment on an LP that was cleaned almost a year ago and stored in a MFSL inner sleeve...no marks, the LP looks as perfect as the day it was cleaned. I was wondering if anyone else has ever experienced this problem? I've been using the sleeve for almost 10 years...almost 2000 LP's in MFSL inners, and have never had this happen before.