Urgent help!! Universal Input Shutdown

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Hello Im currently designing a power supply with the following specs. Controller Topswitch TOP245Y Design: flyback topology Ac Input: 80-277Vac with % over setting the highside line voltage at 305Vac Output Voltage: 12V Output Power: 30W Current limit at 305 roughly 3A Current limit at 120 roughly 2.8A The schematic is basicly the same as the Databook and design guide p2-182 Possible problem parts: current limit R1 6.5Meg R2 15.8k line u/o vol R4 2Meg control R5 6.8 C5 47uF and 100nF cap between control pin and ref grnd The problem: Using a variac to bring the supply up, I get the desired current limits. At 120Vac I can turn the device right on and current limit just fine, but at 277Vac or 305Vac I can get my current limits but turning back on the device not so much. The controller wont even turn right on at 277Vac or 305Vac with no load. But... I can adjust up to 277 or 305 with the variac but as soon as I adjust the load to trip the current limit and remove the load, I have to bring the voltage below about 240Vac before I can get the controller to turn back on... ?? Do ya think its a problem with the above choice of parts? or a stability problem? do ya have some circuit areas I need to scope out?... And why does the current limit increase with increasing line voltage, I would think that as the line voltage went up more current would flow through R1 and R2 and the current limiting pin would source less thus lower current limit at higher voltages. ie. smaller current limit at 305Vac then at 120Vac?? Thanks
former, Universal input is usually means 85VAC to 265VAC. 305VAC is beyond normal universal input range. Please send spreadsheet showing peak drain voltage. If you do not have spreadsheet then send wavefroms of drain voltage and and drain current. You may be overstressing design.