Thanks to everyone who has answered. I don't know if this is a bad way of posting but I have answered everyone together.
Could you please define what you mean by better?
How does the audio quality differ between the two laptops?
How does the audio quality differ between the two programs on the same laptop?
What amplifier and speakers/headphones do you use? Do you use an on-board sound device and the analog output connector or something else?
I assume you are speaking about an obvious difference.....
Sounding "better" is of course my opinion. Sorry I should have said "different". It sounds different in that the JRiver on my laptop has a thinner sound than on my friends. Less Bass and body. This is similar to the difference between JRiver and Mediamonkey on my laptop. JRiver sounds thinner. I appreciate that louder can often sound "better" and I did take that into account.
The system was as follows: Laptop with Win7, Ayre QB9, Silent wire USB cable, Naim Amp and Ovator 600 speakers. The room is also with bass traps, diffusors and absorbers.
I also have the same opinion when playing on my own system: Ayre QB9, Silent Wire USB cable, Swissonor AM6221 Tube Amp and Swissonor BACH 12 speakers. The room has less "correction" applied to it but the difference to me appears to be clear.
If you're outputting via the laptops' 3.5mm audio jacks, the difference may be in the onboard soundcards, and their DACs, or as others have expressed, the volume levels. I suspect the latter if mediaamonkey sounds better to you on your laptop - perhaps the default gain is different on the two programs. Also, since there are so many tweaks one can do in MC, maybe you should load the same library file with a restore on each laptop, and choose to apply the same settings too.
Output is via USB. If I am comparing Mediamonkey with JRiver the volume appears similar, even if I did not check the SPL. Both are outputting music in bitperfet mode so no leveling or volume control is applied from the software.
Try using WASAPI Event Style. Tools/Options/Audio.
If you have ever used Jplay, uninstall it.
Yes I am using WASAPI event style. I do not have Jplay. I am not using the internal soundcard.
I am going to borrow another laptop (but XP instead of W7) and see if the difference is there too.