It's been a few days since I logged on, so I just saw the thread about our night signal on WNTP. For about the past two weeks I have been getting about 5 calls and emails a day about the problem.
Here's the lowdown. The interference is being caused by CKGM in Montreal. CKGM is 50KW fulltime, but normally has a very tight null to the south at night to protect us. I have done extensive field strength readings on them in the past week, and the high level of CKGM's signal in Philly right now would astound you. I know it did me. All one has to do is listen to know that it must be high. I spoke with their CE yesterday, and found out that they have been operating on their fairly loose day pattern at night.
We are working through the powers that be to resolve the situation with CKGM.