Hey everybody! My band has been recording on the a new Tascam 488mk2 for the last four months. We have spent about 50 hours recording and 100 hours of regular tape playing. When we recorded a guitar overdub the other night, we noticed a warbling sound on playback that made the guitar sound like it was underwater. I clean the machine after every recording session and we demagnetized it according to the manual's suggestions. We are using TDK Pro SM30 multitrack tapes. Does anybody have any idea what going on? We hope it's something minor and we definitley don't want to lose the many hours we have spent recording. Thanks for any info!