Jump to content
Get SynergyOpen a support ticket

horrible mouse lag?

Recommended Posts


I don't have the best internet, but i don't believe it is causing the problem (i've attached my speedtest results). With my apartment setup the living room is the only room that has a working coaxial connection, so i can't connect my PC and Mac Mini directly to the router, since they are setup in my bedroom. I did read this article here that there is a specific issue on Mac that my be causing the issue, but i have no idea if it's been fixed and there is no date on the article. Is there anything i can do to fix this?35071884_Screenshot2022-05-02212052.png.41645becb5ea04a8f34ef5bdeacfdd28.png

Link to post
Share on other sites
  • 1 month later...
  • Synergy Team
Daniel Evenson

Hi! 👋

Are you still experiencing this issue? 

It might be related to the port (perhaps a conflict), if you change the port in Preferences (both server and client), does that help?

Also, Synergy does not use the internet to work - only the local LAN network (ie. from your computer to the router). As long as the devices are not too far from the router the connection will be fast/stable enough.

Link to post
Share on other sites
  • 2 weeks later...

I'm also experiencing the same issue after the update to 1.14.3 from 1.14.1: My computers are both connected to the same wifi and is about 3 meters away from the modem/router. The main computer with the keyboard and mouse is a PC and is connecting to a M1 Mac, I've tried changing the ports but that didn't help unfortunately.

Appreciate any help on this!

Edited by JonathanK
Additional information added
Link to post
Share on other sites

I forgot to mention that i am also having issues where both the client and server computers freeze for up to 10 seconds. This happens randomly on the client computer with normal use, but it also triggers after being idle for awhile and then moving the cursor from client computer to server computer and vice versa.

I've gone through a lot of troubleshooting and tried out different recommendations from the forum and they seem to have resolved most of the issues. 

I first ran this command on the client (m1 mac mini) "sudo ifconfig awdl0 down" (undo the command with "sudo ifconfig awdl0 up") this is basically the wifriedx solution. I honestly don't know if this did anything or not.

Next i set all 3 synergy processes to low priority following this thread here:

After that things felt a whole lot smoother and i haven't noticed any freezing, but lag was still present.

So while still using a wifi connection, i decided to switch to a wired connection between the Windows PC and Mac Mini. Follow this thread here: 

So far i am not having any freezing issues and lag is very minimal.

Other Issues:

Clipboard sharing seems to only work with urls, i cannot copy pictures or any other type of file, drag and drop does not work. When pasting a url from server browser into client browser everything freezes for about 10 seconds, i have not found a solution to this yet.

Mouse scrolling on the client computer is very slow even after setting scroll speed to max in accessibility.

This reddit post says changing the logging level from info to warn or error can solve the lagging issues, but i only see Info and Dubug as options in the logging level? 


Link to post
Share on other sites

I'm also experiencing some serious lag on the client side. I am running windows 10 on the server side and connected to an MacbookPro M1 on the client side. Just started happening this morning. Tried to update to the newest version as well as changing the port and it's still happening. Please help :)

Edited by merdz
Link to post
Share on other sites
  • 3 weeks later...

I have this issue as well.

I have a Windows 11 server and a MacbookPro Intel client.  Previous Synergy versions worked well, but version 1.14.4 lags quite a lot.  I have 300+Mb upload and download on wireless so I don't believe wireless is the issue.   However, I have a network adapter ordered and will try wired when I can.

In the meantime, what can we do to mitigate the issue?  I've started using the Mac directly now since the lag is so bad.

Why is version 1.14 so much worse than previous versions?

Please advise.


Link to post
Share on other sites

I have connected a wired network adapter to my Mac, bringing the upload/downloads speeds up to 900+Mb.  The lag issues have disappeared so far.  I still don't understand why I wireless worked well for quite a long time and started failing right after I updated to v1.14.  However, with wired ethernet, the software works well again.

Link to post
Share on other sites
  • 4 weeks later...

Long time user of Synergy here - I have run into these problems in the past as well. Some notes that may help.

- Your external network speeds (speedtest.net results) don't matter unless you are attempting to share the keyboard / mouse / clipboard over a VPN connection. That would probably be pretty slow anyway.

- To get a feel for your local network speed (on windows systems) go to network and sharing center, determine the active connection, click the link in connections. In the populated status page under Connection look for "Speed". This is the negotiated local link speed on your network. But this is only 1/2 the story.

- Even if your negotiated network speed is great there still may be a latency and or route issues that needs to be rooted out. 

- Depending on the network setup you may want to disable TLS / SSL on synergy, if there is any sort of packet inspection going on this will slow it down and cause the lag. (yes this includes home networks, some ISPs have goofy settings on their provided modems) - disabling this or creating a rule to not inspect the traffic has helped me.

- If your system(s) are running multiple connections (wired and wireless) try disconnecting from the wifi - it may be preferring that connection.

- If wireless only disable any performance limiting / energy saving features (EG: Set to maximum performance if able)

Link to post
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now
  • Create New...