<p>Hey Barry,<br />
It is killing the tremolo because you are plugging in an external signal. It sounds like the problem is that the signal is strong enough to trigger the lights but not the tremolo circuit.<br />
Many signals work but we have found that a few devices have a hard time talking to the DroneLab. The solution is to install an input buffer. If you have a little circuit building experience this will relatively be easy. You can either build a simple amplifier or a comparator that takes incoming signals and transforms them into a usable level. I can upload some schematics shortly. If you would like me to do it email me and I'll make you a deal.
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