Hello, My Tascam Porta07 seems to pop out of record and playback mode at random. The longest I've ever been able to record is about 60 seconds. When I tried to play it back it would keep stopping. It really seems to be totally random. Sometimes it works for 15-20 seconds and sometimes 1-2 seconds. It has no other issues. It rewinds and fast forwards fine. The zero stop function is off, but when it's on the tape stops at zero. I'm a newbie, so if I open it up I won't really know what I'm looking at. It seems to be in great shape and came with the box and manual so I'm hoping it can be a simple fix. Thanks so much for any help!