From the SEMARA Repeater Committee:
You may have noticed intermittent crackle noises on weak signals when using the 2m repeater lately. Rick, W1RJC went down to the repeater site this evening to troubleshoot the issue. It was discovered that there is a potential problem with the antenna and/or feedline which is causing the repeater to “desense” (the repeater’s transmitter is getting back into the receiver).
To temporarily remedy the issue and make the repeater more usable, the repeater’s 100 watt amplifier has been turned off and the repeater is currently running 20 watts. The side effect is that the repeater will be slightly weaker on fringe areas, however weaker signals will not be as noisy getting into the repeater. This is an interim solution until the repeater committee has the chance to troubleshoot further.