I'm looking at temporarily moving some equipment on top of some subwoofers. Obviously this would be a potentially vibration issue, but let's assume they're only run very low. What I'm more worried about is the large magnets from the 15" drivers. If I put a laptop on top of these, for example, am I likely to have problems? Other electronics? How likely are the driver magnets to end up causing issues with electronics that are on top of the subwoofers?