not sure what is wrong with this config

Hi all

Lately I had to add 2 new exporters and since then strange things started to happen.
Until now I was using this set of 7 exporterconverters:

ExportConverters =7ExportModality0 =CTExportConverter0 =xx.exeExportModality1 =MRExportConverter1 =xx.exeExportModality2 =CRExportConverter2 =xx.exeExportModality3 =USExportConverter3 =xx.exeExportModality4 =MGExportConverter4 =xx.exe; forward compressed as j2 to AIO;ExportConverter5 = ifequal "%V0032,1033", "CZM"; forward compressed as j2 to FWD;ExportModality6 =PXExportConverter6 =xx.exe

and everything was working as expected.. for years, but as soon as I changed ExportConverters to 9 and added this:

ExportModality7 =CT
ExportCallingAE7 =AN_CT
ExportConverter7 =forward compressed as un to Op1


ExportModality8 =CR
ExportCallingAE8 =NXCRM
ExportConverter8 =forward compressed as un to Op1

strange hang ups started to happen. It works for some time and then suddenly I get a call from CT technicians telling me that they can't send images to pacs... so I restarted service and it works again for few hours.. then again it suddenly stops accepting images.

Am I missing some obvious mistake in config here or..?
dgate ver 1.4.17d