Solution : https://service.sap.com/sap/support/notes/481278 (SAP Service marketplace login required)
Key words : 
//sapserv3/general/r3server/abap/note, current delta requests exist, low-speed processing, long access times, performance problems due, microsoft sql server, sap gui communication, function groups arfc, red traffic light, deleting outbound queues
Related Notes : 
       
| 897807 | CRM 3.1 SP Stack 12 (12/2005): Release & Inf. Note | 
| 844192 | CRM 3.1 SP Stack 11 (06/2005): Release & Inf. Note | 
| 755934 | CRM 3.1 SP Stack 07/2004 (SAPKU31009): Release & Info. Note | 
| 711716 | CRM 3.1 SP Stack 03/2004 (SAPKU31008): Release & Info. Note | 
| 704121 | EBP/CRM 3.0 SP Stack 02/2004 (SAPKU30018): Release&Info.Note | 
| 697884 | Queues in SMQ2 are not processed | 
| 683842 | CRM 3.1 SP Stack 12/2003 (SAPKU31007): Release & Info. Note | 
| 683459 | qRFC performance improvements in the inbound scheduler | 
| 672471 | EBP/CRM 3.0 SP Stack 11/2003 (SAPKU30017): Release&Info.Note | 
| 663180 | Support Release 01 for CRM 3.1 | 
| 653691 | SAPKU31006: Support Package 06 for CRM 3.1 | 
| 646661 | SAPKU30016: Support Package 16 for EBP 3.0/CRM 3.0 | 
| 613440 | Red requests w/ error during PSA loading; RSAR 130 | 
| 609353 | SAPKU30014: Support Package 14 for EBP 3.0/CRM 3.0 | 
| 595862 | P31:P11: Load PSA: RSAR 130 and incomplete loads | 
| 593367 | P31:P11:Red requests with error when loading into PSA | 
| 584926 | QOUT_QIN_MODE_MISMATCH short dump | 
| 582586 | SAPKU30013: Support Package 13 for EBP 3.0/CRM 3.0 | 
| 578842 | UPD WPs have the status CPIC(RFC) stop in SM50 | 
| 565640 | SAPKU31002: Support Package 02 for CRM 3.1 | 
| 561987 | SAPKU30012: Support Package 12 for EBP 3.0/CRM 3.0 | 
| 545613 | SAPKU30011: Support Package 11 for EBP 3.0/CRM 3.0 | 
| 542295 | Direct TO creation when posting material document | 
| 524647 | Performance: Parallel processing of the campaign execution | 
| 504322 | Correction condition tables for usage free goods | 
| 504274 | Kanban: Problem with direct TO creation from transfer req. | 
| 501647 | Supplement 7 of qRFC version 6.20.045 for 3.x,4.x and 6.10 | 
| 498484 | BW extraction: Mult. delta records with qRFC 6.20.043 | 
| 498475 | Error 3 when writing to the PSA | 
| 498211 | Problem with direct TO creation from R/2 | 
| 494216 | Error in queue R3AD_CONNOBJ: Document was not found | 
| 493166 | Error in tRFC/qRFC with confirmation | 
| 491028 | Short dump NO_END_MARKER_FOUND in SAPLERFC | 
| 490805 | Queue restart using background job does not work | 
| 460434 | ConnTrans successful but no data transfer | 
| 460235 | tRFC/qRFC: Low-speed processing | 
| 459151 | Possible termination during data transfer with qRFC | 
| 450366 | SAPKU30007: Support Package 7 for EBP 3.0/CRM 3.0 | 
| 438015 | Latest qRFC version and supplement for 3.x, 4.x, 6.10, 6.20 | 
| 331046 | Quant is already blocked for posting change | 
| 216364 | Blocked queue / No update to external tax system |