Stereo Tool

Hello guys!
I'm trying to use ST 6.10 standalone, because i need to broadcast to FM+Internet, but i have 192 khz Juli@ only. So, i need to use 3 soundcards: 1st - integrated Realtek HD audio (96 khz support) as source, because i need to use player (winamp atm) + some jingle software - i use it as input. Next is 2 outputs: for FM is Juli@ & for Internet broadcasting is C-Media PCI audio (48 khz support). OS is Win server 2003 x86, And i got not very good results of this, CPU is Dual Core 2.6 Ghz, 1 Gb RAM. Main oft I'm using on 1st processor's core, stereo tool on 2nd. Current configuration:
input: Realtek HD audio - s/r: 96000
output fm/rds soundcard: Juli@ Ch12
low quality soundcard: C-Media PCI audio
stereotool.exe cpu loading is 44-49%, ram loading is 31486 KB
After playing 3-5 hours RDS text freeze or unreadable, RDS indicator shown not constantly and I see some HF noise, but if i reset buffer in stereotool, all playing correctly next 3-5 hours. After next 3-4 hours if i didn't reset buffer of stereotool, winamp start full noising (but jingle playing normally !?!). So, what may it be or how can i fix it?

PS: This day I'm experimenting with ST 6.20