Richard Forsyth, 32, had been on trial for almost three weeks having denied 18 offences including rape, attempted rape, sexual assault and assault by penetration, against seven women.
The jury, having heard evidence from his accusers, have been deliberating since Tuesday of this week.
And late on Friday afternoon the jury told Judge Peter Barrie that they could unanimously find Forsyth guilty on six charges of sexual assault, but that there was "no way" they would reach a consensus on the remaining charges.
The judge then discharged the jury and thanked them for their time and commitment, especially under difficult Covid conditions.
Forsyth, of Brookfield Close in Weston Rhyn, has been remanded in custody while the Crown Prosecution Service decides whether to proceed with a re-trial on the remaining 12 charges.
Their decision is due within 14 days.
All 18 of the alleged offences ranged from February to June last year.
The prosecution was represented throughout the trial by Mr Benjamin Lawrence and Forsyth was represented by Mr Paul Smith.