help with oscam, wont record whilst watching another chanel

hi everyone, i have been using Cccam for a long time without any problems but recently my server has been Glitching bad using cccam but switching to Oscam has made the glitching better.. But i have a twin tuner and when i try to record one channel and watch a different channel just shows a black screen or doesnt record , if i go back to Cccam it has no problems at all, i currently have a Unibox with oscam ymod 1859 on it running openatv. anyone able to help