Obviously I can't speak for the OP but I will wade in here nonetheless, as one of the other VM Sky Sports subscribers also suffering from this problem.
First of all, I'm glad to see someone from VM taking an interest.
Like the OP, when using the new Sky Sports player, I am getting very slow frame rate, about 2Hz, plus several second freezes every minute or less, plus a sound problem which seems to me to be the left and right stereo channels having slipped from synchronisation with the picture and with each other. All in all, this makes watching Sky Sports via the player impossible. Since this is my main method of watching SS, and since at my last contract review I was convinced by VM to retain my Sky Sports subscription by the availability of the channels via the portal on Virgin TV Anywhere, I regard this as a severe diminution of the service that I receive. If it can't be fixed or adequately worked around very soon, then for me, this is going to become a refund/retentions issue.
For information, I am using the player, as downloaded late last week from the Sky site, on an ASUS X553S with Intel 4core 3700 at 2.4GHz using Windows 10.
I am having the same problem. I am using a Windows 10 Laptop. Until recently, watching Sky Sports was great, using Silverlight, etc. But since we were all forced to download the new Sky Sports Player, it is unwatchable. The picture and sound either freezes or jumps or play very slowly & stutters. IT IS AWFUL!! This seems to have been going on for far too long now & needs to be sorted out. PLEASE, PLEASE HELP!!!!!!!
I'm having a similar problem. Windows 10 using Sky Sports App on laptop using HDMI to an LG TV. Initially I was getting extreme jumpiness on the sound/picture which was unwatchable. I solved the stuttering pic by accessing the laptop graphics card and reducing the refresh rate for the TV from 59p Hz to 23p Hz (which is the lowest available). However, I now have the sound sync issue. The sound is a bit earlier, so it is watchable but not ideal. I would be interested to hear if anyone has a solution to this sync problem.