CPU overload when Mixxx is started

Hello,
I am experiencing a CPU overload issue that I had not encountered before. I am on Ubuntu Mate 20.4. My machine is a 4-core Xeon (8 Virtual core) and 16 GB Ram. When I run Mixxx (2.2.4) the CPU load is racing (Xorg, Mixxx, kworker). Mixxx becomes unusable and the system lags. I also have a laptop (less powerful) running ubuntu Mate 20.4 and the problem does not appear. Mixxx remains at 20% on my laptop. Do you have any idea of the problem?

I uninstalled / reinstalled Mixxx. I also tried the 2.3 beta version and the problem is the same.

Do you have any idea of my problem?
Thank you very much ?

Below is the activity without Mixxx :

top - 16:09:01 up  6:23,  1 user,  load average: 0,62, 0,72, 0,79
Tasks: 397 total,   1 running, 396 sleeping,   0 stopped,   0 zombie
%Cpu(s):  4,2 us,  2,4 sy,  0,0 ni, 93,4 id,  0,0 wa,  0,0 hi,  0,0 si,  0,0 st
MiB Mem :  15965,9 total,   1269,5 free,   5325,1 used,   9371,3 buff/cache
MiB Swap:   1906,0 total,   1897,2 free,      8,8 used.   9799,7 avail Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                     
  20487 sni       20   0 3924520 691580 217384 S  20,9   4,2  40:46.72 Web Content                                 
  13922 sni       20   0 3960104 566864 215512 S   4,0   3,5  17:34.80 firefox                                     
  11374 sni        9 -11 2534540  18720  14036 S   2,7   0,1   4:14.07 pulseaudio                                  
  14117 sni       20   0  198100  37548  29616 S   2,7   0,2   6:57.37 RDD Process                                 
  20511 sni       20   0 2998984 324792 151272 S   2,3   2,0   2:13.94 Web Content                                 
   2356 root      20   0 1296304  82076  51428 S   2,0   0,5   7:07.69 vmware-hostd                                
  13022 root      20   0  952780 228228 198056 S   2,0   1,4   5:16.20 Xorg                                        
  13890 sni       20   0  483096  43616  31436 S   2,0   0,3   0:17.73 mate-terminal                               
  26186 sni       20   0 8168132   1,0g  87116 S   1,3   6,3   9:34.29 java        

Below is the activity when Mixx is launched :

top - 16:11:38 up  6:25,  1 user,  load average: 2,49, 1,31, 0,99
Tasks: 409 total,   2 running, 407 sleeping,   0 stopped,   0 zombie
%Cpu(s):  5,7 us, 13,2 sy,  0,0 ni, 81,0 id,  0,0 wa,  0,0 hi,  0,0 si,  0,0 st
MiB Mem :  15965,9 total,    834,1 free,   5662,4 used,   9469,4 buff/cache
MiB Swap:   1906,0 total,   1897,2 free,      8,8 used.   9455,9 avail Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                     
  13022 root      20   0  960932 236028 205856 S  70,5   1,4   6:00.41 Xorg                                        
  67295 sni       20   0 6425096 436284 131856 R  54,3   2,7   0:39.76 mixxx                                       
  31156 root      20   0       0      0      0 D  15,6   0,0   0:53.72 kworker/u64:10+events_unbound               
  67354 root      20   0       0      0      0 D   8,6   0,0   0:01.79 kworker/u64:9+events_unbound                
  28788 root      20   0       0      0      0 I   6,0   0,0   1:01.01 kworker/u64:2-btrfs-endio-write             
  67204 root      20   0       0      0      0 I   5,0   0,0   0:03.58 kworker/0:2-events                          
  20487 sni       20   0 3924520 712288 217448 S   3,3   4,4  41:05.39 Web Content