Cannot download filelists consistently

[ugle43 0]

I have a pretty odd problem with ApexDC++, I run to instances, they have the same settings, expect different ports. I use the "manual port forwarding"-settings. All ports are forwarded in my router. My problem is that many times when i open ApexDC++, i cannot download filelists. I can search just fine, and one of the two clients might work but not the second (i do not use the same ports for bot clients). Sometimes it starts to work again if i just quit the client and restart it (work as in maybe 90% of filelists can be downloaded, but not all). In passive mode it always works more or less, but I would rather be in active mode if i can. If I check the connection in Apexdc, it connects to the port just fine. Any idea what can cause this problem? (It seemed to work a lot better in 1.4.2, but in 1.4.3 its worse again, and i also have the problem regardless of what client others are using)